双语练习-常用句子

《国际贸易实务（双语）》三习题库第一章国际贸易简介Chapter 1 A Brief Introduction to International Trade预习题1. What is international trade?2. Why do nations trade?练习题3. What are the differences between international trade and domestic trade?4. P17-20 专业术语、课后练习复习题5. What are the characteristics of international trade？6. What are the forms of international trade？7. Useful certificates for your future job-hunting.第二章进出口交易的一般程序General Procedure of International Trade一、国际贸易的基本流程Basic procedure of international trade预习题：1. Suppose you are an exporter, what will you do before you enter into a business with a trade partner?2.我国某出口公司与香港C公司签订了一笔总值25万美元销售猪肉的合同,FOB青岛,目的港韩国釜山,付款方式为D/A远期120天办理托收。

该出口公司按规定的装运期限装运货物后,通过中国银行办理托收手续。

中国银行委托香港南洋商业银行为代收行向香港C公司收款。

单据到香港后,C公司即承兑赎单,又以原提单向韩国收货人收取了货款。

香港南洋商业银行在汇票到期时向C公司催促付款,但此时该公司已宣告破产。

经查核C公司在当地注册资本仅15万港元,其财产远远不够抵偿该公司的欠款。

Quiz for Chapter 12Ⅰ. Fill the following blanks with the proper word or expression1. Y-( )=CA2、National income equals GNP less ( ),plus ( ),less ( ).3. GNP equals GDP ( ) net receipts of factor income from the rest of the world.4. The national income identity for an open economy is ( ).5. When a country 's exports exceed its imports, we say the country has a current account ( ).6. The current account includes ( )7. Any transaction resulting in a payment to foreigners is entered in the balance of payment account as a ( ).8. In a closed economy, national saving always equals ( ).9.When official reserves increase, this will be recorded in the ( ), with ( )sign.10. When debit is bigger than net decrease of the reserve, the difference will go to the ( ).Ⅱ. True or false1. The balance of payments accounts always balance in practice as they must in theory.( )2. Net unilateral transfers are considered part of the current accounts but not a part of national income .( )3. The GNP a country generates over some time period must equal its national income ,the income earned in that period by its factors of production. ( )4. When you buy a share of Microsoft stock , you are buying neither a good or a service , so your purchase dose not show up in GNP. ( )5. If the government deficit rises and private saving and investment do not change much ,the current account surplus must fall by roughly the same account as the increase in the fiscal deficit. ( )6. We include income on foreign investment in the current account because that income really is compensation for the services provided by foreign investments.( )7. Remember that foreign borrowing may not always be a bad idea :a country that borrows abroad to undertake profitable domestic investment can pay its creditors and still have money left over.( )8. Government agencies including central banks can freely hold foreign reserves and intervene officiallyin exchange market.( )9. When the United States lends abroad, a payment is made to foreigners and the capital account is credited.10. One reason intervention is important is that central banks use it as a way of altering the amount of money in circulation.Ⅲ. Answer the following questions:1.Why account keepers adds the account a statistical discrepancy to the balance of payment?2.The nation of Pecunia had a current account deficit of ＄1 billion and a nonreserve financial account surplusof ＄550 million in 2005.(1)What was the balance of payments of Pecunia in that year? What happened to the country’s net foreignassets?(2)Assume that foreign central banks neither buy nor sell Pecunian assets. How did the Pecunian central bankshad purchased ＄600 million of Pecunian assets in 2005? How would this official intervention show up in the balance of payments accounts?(3)How would your answer to (2) change if you learned that foreign central banks had purchased enter foreignbalance of payments accounts?Ⅳ. Fill the following blanks:China's balance of payment in 2000Quiz for Chapter 13Ⅰ. Fill the following blanks with the proper word or expression1. Changes in exchange rates are described asor .2. Foreign exchange deals sometimes specify a value date farther away than two-days-30 days, 90days, 180 days, or even several years. The exchange rates quoted in such transactions are called3. is the most liquid of assets4. The ease with which the asset can be sold or exchange for goods, we call the character is5. A foreignis a spot sale of a currency combined with a forward repurchase of the currency.6. The foreign exchange market is inwhen deposits of all currencies offer the same expected rate of return.7. The price of one currency in terms of another is called an8. All else equal, ain the expected future exchange rate causes a rise in the current exchange rate.9. is the percentage increase in value, it offers over some time period.10. All else equal, anin the interest paid on deposits of a currency causes that currency to appreciate againstforeign currencies.Ⅱ. True or false1. A rate of appreciation of the dollar against the euro is the rate of depreciation of the euro against dollar.( )2. The exchange rate quoted as the price of foreign currency in terms of domestic currency is called direct quotation. ( )3. all else equal, an appreciation of a country's currency makes its goods cheaper for foreigners. ( )4. The foreign exchange market is in equilibrium when deposits of all currencies offer the same expected rate of return. ( )5. All else equal., When a country's currency depreciated, domestic residents find that imports from abroad are more expensive. ( )6. Central bank is at the center of the foreign exchange market.( )7. A depreciation of the dollar against euro today makes euro deposit less attractive on the condition that expected future dollar/euro rate and interest rates do not change.( )8. all else equal, a decrease of the interest paid on deposit of US dollars causes dollars to appreciate against foreign currency.( )9. New York. is the largest foreign exchange market in the world. ( )10. A fall in the expected future exchange rate causes a fall in the current exchange rate.Ⅲ. Answer the following questions:1. Currently, the spot exchange rate is US$1=SF1.50 and the expected exchange rate for six month is SF1.55. the interest rate is 8% in the US per annum and 10% in the Switzerland per annum. （1）Determine whether interest rate parity is currently holding.（2）If it is not holding, what will happen in the foreign exchange market?.（3）If the expected exchange rate is unchanged, what is the spot rate when foreign exchange rate is inequilibrium?2.Suppose the dollar interest rate and the pound sterling interest rate are the same, 5 percent per year. What is the relation between the current equilibrium ＄/￡exchange rateand its expected future level? Suppose the expected future ＄/￡exchange rate, ＄1.52 per pound, remains constant as Britain’s interest rate rises to 10 percent per year. If the U.S. interest rate also remains constant, what is the new equilibrium ＄/￡exchange rate?Quiz for Chapter 14Ⅰ. Fill the following blanks with the proper word or expression1. M1 includes __________.2. An economy 's money supply is controlled by _________________.3. Three main factors that determine aggregate money demand are4. When money supply equals money demand, we say that the money market is _______________________.5. A rise in the average value of transactions carried out by a household or firm cause its demand for money to.6. is an important phenomenon because it helps explain why exchange rates move so sharply from day to day.7. If the economy is initially at full employment, a permanent increase in the money supply eventually be followed byin the price level.8. Overshooting is a direct consequence of the short-run9. An economy’sis the position it would eventually reach if no new economic shocks occurred during the adjustment to full employment.10. All else equal, a permanent in a country’s money supply causes a proportional long-rundepreciation of its currency against foreign currencies.Ⅱ. True or false1. An increase in real output lowers the interest rate. ( )2. In the short run, a reduction in a country's money supply causes its currency to appreciate in the foreign exchange market. ( )3. All else equal, an increase in a country 's money supply causes a proportional increase in its price level in the long run. ( )3. All else equal, a rise in the interest rate causes the demand for money to fall. ( )4. If there is initially an excess demand of money, the interest rate falls in the short-run. ( )5. A rise in the average value of transactions carried out by a household or firm causes its demand for money to fall. ( )6. Given the price level and out put, an increase in the money supply lowers the interest rate. ( )7. A change in the supply of money has effect on the long-run values of the interest rate or real output. ( )8.The higher the interest rate, the more you sacrifice by holding wealth in the form of money. ( )9. An increase in real output lowers the interest rate, given the price level and the money supply( )10. An economy experiences inflation when its price level is falling. ( )Ⅲ. Answer the following questions:1. What is the short-run effect on the exchange rate when US government increases the money supply? (expectations about future exchange rate are unchanged)2.Please draw a group of pictures to show the time paths of U.S. economic variables after a permanent increase in the U.S. money supply growth rate according to the following:(1)The u.s. decided to increase the money supply growth rate permanently.The vertical axis is money supply and the horizontal axis is time.(2)The interest rate change,. The vertical axis is Dollar interest rate and the horizontal axis is time.(3)The price level change. The vertical axis is U.S price level and the horizontal axis is time.(4)The exchange rate change,. The vertical axis is the Dollar/Euro exchange rate and the horizontal axis is time.Ⅳ. CALCULATIONSuppose that the spot rate is €1 = US$1.2468 －78 and the six-month forward rate is €1 = US$1.2523－33, the interest rate per annum is 4% in the euro zone and 6% in the US. After carrying out interest arbitrage with €5,000,000 borrowed at the above-mentioned rate, please calculate your net interest arbitrage profit ( other costs ignored ).Quiz for Chapter 15Ⅰ. Fill the following blanks with the proper word or expression1. The equation for real interest parity is.2. The long-run relationship between inflation and interest rates is called .3. The equation for absolute PPP is _________________________.4. The equation for relative PPP is _________________________.5. The law of_______________ states that under free competition and in the absence of trade impediments, a good must sell for a single price regardless of where in the world it is sold.6. Equation$/$/()/E US q E P P ∈∈=⨯ shows that at unchanged output prices, nominal depreciation implies real.7. According to Fisher effect, if U.S. inflation were to rise, then U.S. dollar interest rates would_________________.8. _________________is the relative price of two output baskets, while _________________is the relative price of two currencies.9. Transport costs and government trade restrictions make it expensive to move goods between markets located in different countries and therefore weaken the _________________mechanism underlying PPP. 10. refer to those goods and services that can never be traded internationally at a profit.Ⅱ. True or false1. According to monetary approach, a rise in the interest rate on dollar will lead to the depreciation of the dollar in the long run.( )2. According to monetary approach, a rise in European output causes the Euro to appreciate. ( )3. When demand for American products rises, there will be a long-run real depreciation of the dollar. ( )4. According to monetary approach, a rise in European output causes the Euro to appreciate. ( )5. When European output supply increases, there will be an appreciation of the euro. ( )6. Expected real interest rates are the same in different countries when relative PPP is expected to hold. ( )7. Based on the monetary approach, other things equal, a permanent rise in the U.S. money supply causes a proportional long-run appreciation of the dollar against euro. ( )8. At unchanged output prices, nominal depreciation implies real appreciation. ( )9. Departures from PPP may be even greater in the short run than in the long run because many prices in the economy are sticky and take time to adjust fully. ( )10. If all U.S. prices increase by 10% and the dollar depreciates against foreign currencies by 10%, absolute PPP will be satisfied (assuming there are no changes abroad) for any domestic and foreign choices of price level indexes. ( )Ⅲ. Answer the following questions :1. Suppose America’s inflation rate is 6% over one year, but the inflation rate in Italy is 12%. According to relative PPP, what should happen over the year to the dollar ’s exchange rate against the lira?2.How to explain the problems with PPP? Give the reasons.Quiz for Chapter 16Ⅰ. Fill the following blanks with the proper word or expression1. The aggregate demand for an open economy’s output consists of four components:2. The current account balance is determined by two main factors: and3. Equilibrium in the economy as a whole requires equilibrium in theas well as in the4. An temporary increase in the money supply causes aof the domestic currency, of output,and thereforein employment.5. Given a fixed exchange rate, when government demand increases, DD schedule will shift6. A reduction in money demand would shift AA ___________.7. __________ policy works through changes in government spending or taxes.8. If the economy starts at long-run equilibrium, a permanent change in fiscal policy has no net effect on .9. J-curve effects amplify the of exchange rates10. Because a permanent fiscal expansion changes exchange-rate expectations, the effect on output isif the economy stats in long-run equilibrium.Ⅱ. True or false1. If there is a decline in investment demand, the DD schedule will shift to the right. ( )2. The effect of real exchange rate increase on IM is ambiguous. ( )3. A temporary increase in the money supply, which does not alter the long-run expected exchange rate, causes a depreciation of the currency and a rise in output. Temporary fiscal expansion also has the same result. ( )4. Other things equal, a real depreciation of the home currency lowers aggregate demand for home output. ( )5. The DD Schedule shows all exchange rate and output levels at which the outputmarket is in short-run equilibrium. DD Schedule slopes upward. ( )6. A permanent fiscal expansion does not changes exchange-rate expectations. ( )7. Since the effect is the same of that of an increase in G, an increase in T must cause the DD Schedule to shift rightward. ( )8. A rise in R* causes an upward shift of AA. ( )9. Either an increase in the money supply or temporary fiscal ease can be used to maintain full employment. The two polices have no different effects at all. ( )10.If exports and imports adjust gradually to real exchange rate changes, the current account may follow a J-curve pattern after a real currency appreciation, first worsening and then improving. ( )11. The greater the upward shift of the asset market equilibrium schedule, the greater the appreciation of the currency. ( )12. Monetary expansion causes the current account balance to decrease in the short run. ( )13. Expansionary fiscal policy reduces the current account balance. ( )Ⅲ. Answer the following questions:1. A new government is elected and announces that once it is inaugurated, it will increase the money supply. Use the DD-AA model to study the economy’s response to this announcement.2. Please use AA and DD schedules to describe “The adjustment to a permanent increase in the money supply. ” The original point is at full employment.The vertical axis is exchange rate, the horizontal axis is output.3. If an economy does not start out at full employment,is it still true that a permanent change in fiscal policy has no current effect on output? Please use AA and DD schedules to describe it.Quiz for Chapter 17Ⅰ. Fill the following blanks with the proper word or expression1. Any central bank purchase of assets automatically results in an in the domestic money supply.2. The condition of the foreign exchange market equilibrium under a fixed exchange rate is .3. Under a fixed exchange rate, central bankpolicy tools is more effective.4. The expectation of a future devaluation causes ain the home interest rate above the world level.5. The main factor that may lead to imperfect asset substitutability in the foreign exchange market is .6. Between the end of World War II and 1973, was the main reserve currency.7. Under a gold standard, each country fixes the price of its currency in terms of .8. Under a _________, central bank monetary policy tools are powerless to affect the economy’s money supply or its output.9. A system which governments may attempt to moderate exchange rate movements without keeping exchangerates rigidly fixed is____________.10. Half way between the gold standard and a pure reserve currency standard is the __________.Ⅱ. True or false1. Any central bank sale of assets automatically causes the money supply to decline. ( )2. If central banks are not sterilizing and the home country has a balance of payments surplus, any increase in the home central bank’s foreign assets implies an decreased home money supply. ( )3. Under a fixed exchange rate, central bank monetary policy tools are powerful to affect the economy’s money supply. ( )4. The expectation of a future revaluation causes a rise in foreign reserves. ( )5 When domestic and foreign currency bonds are imperfect substitutes, equilibrium in the foreign market requires that the domestic interest rate equal the expected domestic currency return on foreign bonds subtract a risk premium. ( )6. Between the end of World War II and 1973, the exchange rate system was one in which exchange rate between any two currencies were floating. ( )7.Under the reserve currency standard, the center country has to intervene the exchange rate. ( )8. The central bank can negate the money supply effect of intervention through sterilization.( )9. A system of managed floating allows the central bank to retain some ability to control the domestic money supply, but at the cost of greater exchange rate instability.( )10. A world system of fixed exchange rates in which countries peg the prices of their currencies in terms of a reserve currency does not involve a striking asymmetry.()Ⅲ. Answer the following questions:1. Why governments sometimes choose to devalue their currencies?2. How does fiscal expansion affect a country’s output and the central bank’s balance sheet under fixed exchange rate?3. Can you think of reasons why a government might willingly sacrifice some of its ability to use monetary policy so that it can have stable exchange rates?4. Explain why temporary and permanent fiscal expansions do not have different effects under fixed exchange rates, as they do under floating.Quiz for Chapter 18—21Ⅰ. Fill the following blanks with the proper word or expression1. The channels of interdependence depend, in turn, on the monetary and exchange rate arrangements that countries adopt-a set of institutions called the （）.2. In open economies, policymakers are motivated by the goals of internal and external balance. Simply defined, ( )requires the full employment of a country’s resources and domestic price level stability.3. A country is said to be in( ) when the sum of its current and its no reserve capital accounts equals zero, so that the current account balance is financed entirely by international lending without reserve movements.4. The gold standard contains some powerful automatic mechanisms that contribute to the simultaneous achievement of balance of payments equilibrium by all countries .That mechanisms is( ).5. ( ) is one currency that may be freely exchanged for foreign currencies.6、Under the Bretoon Woods system ,( ) or ( )can be used to influence output and thus help the government achieve its internal goal of full employment.7、Fiscal policy is also called ( ),because it alters the level of the economy’s total demand for goods and services.; The accompanying exchange rate adjustment is called ( ), Because it changes the direction of demand ,shifting it between domestic output and imports.8、Bretton Woods system give ( )the leading position in the world economy.9、Bretton Woods system require that other currency should peg with ( )10、Under the fixed rate system, if the exchange rate change, the foreign reserves will ( )11、( ) symmetry and exchange rate as automatic stabilizers are the advantages of floating rate system.12、( ) predict the collapse of the Bretton Woods system.13、The level of ( ) in the European Union is too small to cushion member countries from adverse economic events.14、The ( ) schedule shows the relationship between the monetary efficiency gain and the degree of economic integration.Ⅱ. True or false1. In an open economy, macroeconomic policy has two basic goals, internal balance (full employment with price stability) and external balance (avoiding excessive imbalances in international payments)( )2. The gold standard era starts in 1861 and end in 1914.( )3. The countries with the weak investment opportunities should be net importers of currently available output (and thus have current account surpluses), while countries with the good investment opportunities should be net exporters of current output (and have current account deficits).( )4. Each member of IMF contributed to the Fund an amount of gold equal in value to three-fourth of its quota. The remaining one-fourths of its quota took the form of a contribution of its own national currency. ( )5、Balance of payment crisis became increasingly frequent and violent throughout the 1960 and early 1970s.The events led to the Bretoon Woods system’s collapse.（）6、One interpretation of the Bretoon Woods system’s collapse is that the foreign countries were forced to import US. Inflation through the mechanism to stabilize their price levels and regain internal balance, they had toabandon fixed exchange rates and allow their currency to float.（）7、Speculation on changes in exchange rats could lead to instability in foreign exchange markets . （）8.Under the fixed rate system, the government is required to use foreign reserve to stabilize exchange rate.（）9.The U.S. Federal Reserve played the leading role in determining their owns domestic money supply.（）10.Advocates of floating argued that floating rates would allow each country to choose its own desired long-run inflation rate rather than passively importing the inflation rate established abroad. （）11.The eight original participant in the EMS’s exchange rate mechanism------France, German, Italy, Belgium, Denmark, Ireland, Luxembourg, and the Netherlands. ( )。

Chapter 1 Particle KinematicsI) Choose one correct answer among following choices1. An object is moving along the x-axis with position as a function of time given by x=x(t). Point O is at x=0. The object is definitely moving toward O when A. 0<dt dx B. 0>dtdx C. 0)(2<dt x d D. 0)(2>dt x d 2. An object starts from rest at x=0 when t=0. The object moves in the x direction with positive velocity after t=0. The instantaneous velocity and average velocity are related by A. v v < B. v v = C. v v > D. dt dx can be larger than, smaller than, or equal to tx 3. An object is moving in the x direction with velocity )(t v x , anddt dv x is nonzero constant. With 0=x v when t=0, then for t>0 the quantity dtdv v x x is A. Negative. B. Zero. C. Positive.D. Not determined from the information given.4. An object is moving on the xy-plane with position as a function of time given by r = a t 2 i + b t 2 j (a and b are constant). Which is correct?A. The object is moving along a straight line with constant speed.B. The object is moving along a straight line with variable speed.C. The object is moving along a curved path with constant speed.D. The object is moving along a curved path with variable speed. 5. An object is thrown into the air with an initial velocity )8.99.4(0j i v +=m /s . Ignore the air resistance (空气阻力). At the highest point the magnitude of the velocity is ( )(A) 0 (B) 4.9m/s (C) 9.8m/s (D)22)8.9()9.4(+ m/s6. Two bodies are falling with negligible air resistance, side by side, above a horizontal plane. If one of the bodies is given an additional horizontal acceleration during its descent, itA. strikes the plane at the same time as the other body.B. strikes the plane earlier than the other body.C. has the vertical component of its velocity altered.D. has the vertical component of its acceleration altered.7. A toy racing car moves with constant speed around the circle shown below. When it is at point A its coordinates are x=0, y=3m and its velocity is 6m/s i . When it is at point B its velocity and acceleration are:A. -6m/s j and 12m/s2i , respectively. B. 6m/s j and -12m/s 2 i , respectively. C. 6m/s j and 12m/s 2i , respectively. D. 6m/s j and 2m/s 2 i, respectively.8. A stone is tied to a 0.50-m string and whirled at a constant speed of 4.0m/s in a vertical circle. Its acceleration at the bottom of the circle is:A. 9.8m/s 2, upB. 9.8m/s 2, downC. 8.0m/s 2, upD. 32m/s 2, up9. A boat is able to move through still water at 20m/s. It makes a round trip to a town 3.0 km upstream. If the river flows at 5m/s, the time required for this round trip is:A. 120 sB. 150 sC. 200 sD. 320 s II) Fill in the empty space with correct answer1. A particle goes from x =-2m, y =3m, z =1m to x =3m, y =-1m, z =4m. Its displacement is : .2. The x-component of the position vector of a particle is shown in the graph in Figureas a function of time. (a) The velocity component v x at the instant 3.0 s is .(b) When is the velocity component zero ? The time is .(c) Is the particle always moving in the same direction along thex-axis? .3. The angle turned through by a wheel is given by θ＝at +bt 2, where a and b areconstants. Its angular velocity ω＝ , and its angular acceleration β＝ .4. When a radio wave impinges on the antenna of your car, electrons in the antenna move back and forth along the antenna with a velocitycomponent v x as shown schematically in Figure . Roughlysketch the same graph and indicate the time instants when(a) The velocity component v x is zero;(b) The acceleration component a x is zero;(c) The acceleration has its maximum magnitude.5. A car is traveling around a banked, circular curve of radius 150 m on a test track. At the instant when t=0s, the car is moving north, and its speed is 30.0 m/s but decreasing uniformly, so that after 5.0 s its angular speed will be 3/4 that it was when t=0s. The angular speed of the car when t=0s is , the angular speed 5.0 s later is , the magnitude of the centripetal acceleration of the car when t=0s is , the magnitude of the centripetal acceleration of the car when t=5.00s is , the magnitude of the angular acceleration is , the magnitude ofthe tangential acceleration is .6. A projectile is launched at speed v 0 at an angle θ (withthe horizontal) from the bottom of a hill of constant slope βas shown in Figure. The range of the projectile up the slopeis .III) Calculate Following Problems:1. An object with mass m initially at rest is acted by a force j t k i k F 21+=, where k 1and k 2 are constants. Calculate the velocity of the object as a function of time.2. You are operating a radio-controlled model car on a vacant tennis court. Your position is the origin of coordinates, and the surface of the court lies in the xy-plane. The car, which we represent as a point, has x- and y-cooridnates that vary with time according to x=2.0m-(0.25m/s 2)t 2 , y=(1.0m/s)t+(0.025m/s 3)t 3 .a. Find the car ’s instantaneous velocity at t=2.0s.b. Find the instantaneous acceleration at t=4.0s.3. An object moves in the xy-plane. Its acceleration has components a x =2.50t 2 and a y =9.00-1.40t. At t=0 it is at the origin and has velocity j i v 00.700.10+=.Calculate the velocity and position vectors as functions of time.4. An automobile whose speed is increasing at a rate of 0.600 m/s 2 travels along a circular road of radius 20.0 m. When the instantaneous speed of the automobile is 4.00 m/s, find (a) the tangential acceleration component, (b) the radial acceleration component, and (c) the magnitude and direction of the total acceleration.5. Heather in her Corvette accelerates at the rate of (3.00i -2.00j) m/s 2, while Jill in her Jaguar accelerates at (1.00i +3.00j ) m/s 2. They both start from rest at the origin of an xy coordinate system. After 5.00 s, (a) what is Heather’s speed with respect to Jill, (b) how far apart are they, and (c) what is Heather’s acceleration relative to Jill? Chapter 2 Newton ’s laws of motionI) Choose one correct answer among following choices1. In the SI , the base units (基本单位) for length, mass, time are ( )(A) meters, grams, seconds. (B) kilometers, kilograms, seconds.(C) centimeters, kilograms, seconds. (D) meters, kilograms, seconds.2. Which one of the following has the same dimension (量纲) as time ( )(A)a x (B) a x 2 (C) xv (D) vx 3.Which of the following quantities are independent (无关) of the choice of inertial frame (惯性系)?(A)v (B)P (C)F (D) W4. Suppose the net force F on an object is a nonzero constant. Which of the following could also be constant?A. Position.B. Speed.C. Velocity.D. Acceleration. 5. An object moves with a constant acceleration a . Which of the following expression is also constant? ( ) (A)dt v d (B) dt v d (C) dtv d )(2 (D) dt v v d )( 6. An object moving at constant velocity in an inertial frame must:A. have a net force on it.B. eventually stop due to gravity.C. not have any force of gravity on it.D. have zero net force on it.7. A heavy ball is suspended as shown. A quick jerk on the lower string will break that string but a slow pull on the lower string will break the upper string. The first result occurs because:A. the force is too small to move the ballB. action and reaction is operatingC. the ball has inertiaD. air friction holds the ball back8. A constant force of 8.0 N is exerted for 4.0 s on a16-kg object initially at rest. The change in speed of this object will be:A. 0.5m/sB. 2m/sC. 4m/sD. 8m/s9. A wedge rests on a frictionless horizontal table top. Anobject with mass m is tied to the frictionless incline of thewedge as shown in figure. The string is parallel to theincline. If the wedge accelerates to the left, when theobject leaves the incline, the magnitude of its acceleration isA. gsin θB. gcos θC. gtan θD. gcot θ10. A crane operator lowers a 16,000-N steel ball with a downward acceleration of 3m/s 2. The tension force of the cable is:A. 4900NB. 11, 000NC. 16, 000ND. 21, 000N11. A 1-N pendulum bob is held at an angle θ from the verticalby a 2-N horizontal force F as shown. The tension in the stringsupporting the pendulum bob (in newtons) is:A. cos θB. 2/ cos θC. 5D. 112. A car moves horizontally with a constant acceleration of 3m/s 2. A ball is suspended by a string from the ceiling of the car. The ball does not swing, being at rest with respect to the car. What angle does the string make with the vertical?A. 17◦B. 35◦C. 52◦D. 73◦13. A 32-N force, parallel to the incline, is required to push a certain crate at constant velocity up a frictionless incline that is 30◦ above the horizontal. The mass of the crateis:A. 3.3kgB. 3.8kgC. 5.7kgD. 6.5kg II) Fill in the empty space with correct answer 1. A 2.5 kg system has an acceleration 2)4(s m i a =. There are two forces acting onthe system, and One of the forces is N j i F )63(1 -=. The other force is .2. Two masses, m 1 and m 2, hang over an ideal pulley and the system is free to move. The magnitude of the acceleration aof the system of two masses is . The magnitude of the tension in the cord is .3. You are swinging a mass m at speed v around on astring in circle of radius r whose plane is 1.00 m abovethe ground as shown in Figure. The string makes anangle θ with the vertical direction.(a) Apply Newton’s second law to the horizontal andvertical direction to calculate the angle θ is .(b) If the angle θ = 47.4° and the radius of the circle is1.50 m, the speed of the mass is .(c) If the mass is 1.50 kg, the magnitude of the tensionin the string is .(d) The string breaks unexpectedly when the mass is movingexactly eastward. The location the mass will hit the groundis . III) Calculate Following Problems:1. A wedge with mass M rests on a frictionless horizontal tabletop. A block with mass m is placed on the wedge, and ahorizontal force F is applied to the wedge. What must be the magnitude of F if the block is to remain at a constant height above the table top?2. The mass of blocks A and B in Figure are 20.0kg and 10.0kg, respectively. The blocks are initially at rest on the floor and are connected by a massless string passing over a massless and frictionless pulley. An upward force F is applied to the pulley. Find the accelerations a 1 ofblock A and a 2 of block B when F is(a) 124N ; (b) 294N ; (c) 424N.3. An object is drop from rest. Find the function of speed withrespect to time and the terminal speed. Assuming that the drag forceis given by D = bv 2.4. A small bead can slide without friction on a circular hoop that is ina vertical plane and has a radius of 0.100m. The hoop rotates at aconstant rate of 4.00rev/s about a vertical diameter.(a) Find the angle β at which the bead is in vertical equilibrium.(b) Is it possible for the bead to “ride ” at the same elevation as thecenter of the hoop?(c) What will happen if the hoop rotates at 1.00rev/s.Chapter 3 Linear momentum, Conservation of momentum I) Choose one correct answer among following choices1. An object is moving in a circle at constant speed v . The magnitude of the rate of change of momentum of the objectA. is zero.B. is proportional to v .C. is proportional to v 2.D. is proportional to v 3.2. If the net force acting on a body is constant, what can we conclude about its momentum? A. The magnitude and/or the direction of P may change. B. The magnitude of P r remains fixed, but its direction may change. C. The direction of P remains fixed, but its magnitude may change. D. P remains fixed in both magnitude and direction.3. If I is the impulse of a particular force, what is dt I d / ?A. The momentumB. The change in momentumC. The forceD. The change in the force4. A variable force acts on an object from 0=i t to f t . The impulse of the force is zero. One can conclude that A. 0=∆r and 0=∆P . B. 0=∆r but possibly 0≠∆P . C. possibly 0≠∆r but 0=∆P . D. possibly 0≠∆r and possibly 0≠∆P .5. A system of N particles is free from any external forces. Which of the following is true for the magnitude of the total momentum of the system?A. It must be zero.B. It could be non-zero, but it must be constant.C. It could be non-zero, and it might not be constant.D. The answer depends on the nature of the internal forces in thesystem.6. The x and y coordinates of the center of mass of thethree-particle system shown below are:A. 0, 0B. 1.3m, 1.7mC. 1.4m, 1.9mD. 1.9m, 2.5m7. Block A, with a mass of 4 kg, is moving with a speed of2.0m/s while block B, with a mass of 8 kg, is moving in theopposite direction with a speed of 3m/s. The center of mass ofthe two block-system is moving with a velocity of:A. 1.3m/s in the same direction as A.B. 1.3m/s in the same direction as B.C. 2.7m/s in the same direction as A.D. 1.0m/s in the same direction as B.8. A large wedge with mass of 10kg rests on a horizontal frictionless surface, as shown. A block with a mass of 5.0kg starts from rest and slides down the inclinedsurface of the wedge, which is rough. At one instantthe vertical component of the block ’s velocity is3.0m/s and the horizontal component is 6.0m/s. Atthat instant the velocity of the wedge is:A. 3.0m/s to the leftB. 3.0m/s to the rightC. 6.0m/s to the rightD. 6.0m/s to the left9. A 1.0-kg ball moving at 2.0m/s perpendicular to a wall rebounds from the wall at1.5m/s. The change in the momentum of the ball is:A. zeroB. 0.5N · s away from wallC. 0.5N · s toward wallD. 3.5N · s away from wallII) Fill in the empty space with correct answer1. Two objects, A and B , collide (碰撞). A has a mass of kg m A 2=, and B has a mass of kg m B 4=. The velocities before the collision are )32(j i v A +=m /s and )24(j i v B +=m /s . After the collision, )23(j i v A +='m /s . The final velocity of B ='B v m /s .2. A stream of water impinges on(撞击) a stationary “dished ”turbine blade, as shown in Fig.8. The speed of the water is v ,both before and after it strikes the curved surface of the blade,and the mass of water striking the blade per unit time is constantat the value dt dm /=μ. The force exerted by the water on theblade is ___________.3. A 320g ball with a speed v of 6.22m/s strikes a wall at angle θ of 30.0o and then rebounds with the same speed and angle. It is in contact with the wall for 10.4 ms.(a) The impulse was experienced by the wall is .(b) The average force exerted by the ball on the wall is .4. The muzzle speed of a bullet can be determined using a devicecalled a ballistic pendulum, shown in Figure. A bullet of mass mmoving at speed v encounters a large mass M hanging vertically asa pendulum at rest. The mass M absorbs the bullet. The hangingmass (now consisting of M + m) then swings to some height habove the initial position of the pendulum as shown. The initialspeed v ′of the pendulum (with the embedded bullet) after impactis . The muzzle speed v of the bullet is .III) Calculate Following Problems:1. A block of mass m 1=1.60kg initially moving to the right with a speed of 4.00 m/s on a frictionless horizontal track collides with a spring attached to a second block of mass m 2=2.10kg initially moving to the left with a speed of 2.50 m/s, as shown in Figure. The spring constant is 600 N/m.(a) At the instant block 1 is moving to the right with a speed of 3.00 m/s, as in Figure, determine the velocity of block 2.(b) Determine the distance the spring is compressed at that instant.2. A3.00-kg steel ball strikes a wall with a speed of 10.0m/s at an angle of 60.0° with the surface. It bounces offwith the same speed and angle. If the ball is in contactwith the wall for 0.200 s, what is the average forceexerted on the ball by the wall?3. A small ball with mass m is released from rest at thetop of a container which inside wall is semicircle-shapedand frictionless. The container with mass M and radius R rests on a frictionless horizontal surface, as shown. When the ball slides to point B at the bottom of the container, find the normal force exerted by the container on the ball.Chapter 4 Work and EnergyI) Choose one correct answer among following choices1. The work done by gravity during the descent of a projectile:A. is positiveB. is negativeC. is zeroD. depends for its sign on the direction of the y axis2. A particle has a constant kinetic energy E k . Which of the following quantities must also be constant? ( )(A)r (B) v (C) v (D) P3. A 0.2kg block slides (滑行) across a frictionless floor with a speed of 10 m /s . The net work done on the block is ( )(A) -20J (B) -10J (C) 0J (D) 20J4. A 0.50kg object moves in a horizontal circular track with a radius of 2.5m. An external force of 3.0N, always tangent to the track, causes the object to speed up as it goes around. The work done by the external force as the mass makes one revolution is:A. 24 JB. 47 JC. 59 JD. 94 J5. A man pushes an 80-N crate a distance of 5.0m upward along a frictionless slope that makes an angle of 30◦ with the horizontal. His force is parallel to the slope. If the speed of the crate decreases at a rate of 1.5m/s 2, then the work done by the man is:A. −200 JB. 61 JC. 140 JD. 200 J6. When a certain rubber band is stretched a distance x, it exerts a restoring force of magnitude F = a x+b x 2, where a and b are constants. The work done in stretching this rubber band from x = 0 to x = L is:A. a L 2 + b Lx 3B. a L + 2b L 2C. a + 2b LD. a L 2/2 +b L 3/37. An ideal spring is hung vertically from the ceiling. When a 2.0-kg mass hangs at rest from it the spring is extended 6.0cm from its relaxed length. A downward external force is now applied to the mass to extend the spring an additional 10cm. While the spring is being extended by the force, the work done by the spring is:A. −3.6JB. −3.3JC. 3.6 JD. 3.3J8. Two objects with masses of m 1 and m 2 have the same kinetic energy and are both moving to the right. The same constant force F is applied to the left to both masses. If m 1 = 4m 2, the ratio of the stopping distance of m 1 to that of m 2 is:A. 1:4B. 4:1C. 1:2D. 1:19. At time t = 0 a 2-kg particle has a velocity of (4m/s)i − (3m/s)j. At t = 3s its velocity is (2m/s)i + (3m/s)j . During this time the work done on it was:A. 4 JB. −4JC. −12 JD. −40 J10. A 2-kg block starts from rest on a rough inclined plane that makes an angle of 60o with the horizontal. The coefficient of kinetic friction is 0.25. As the block goes 2.0m down the plane, the mechanical energy of the Earth-block system changes by:A. 0B. −9.8JC. 9.8JD. −4.9 J II) Fill in the empty space with correct answer1. A chain (链条) is held on a frictionless table withone-fourth of its length hanging over the edge, as shown infigure. If the chain has a length L and a mass m , the work required to pull the hanging part back on the table isJ .2. A 0.1kg block is dropped from a height of 2m onto a spring offorce constant k = 2N/m, as shown. The maximum distance thespring will be compressed is _________m . (g=10m/s 2)3. A single constant force j i F 53+=N acts on a4.00-kg particle.(a) If the particle moves from the origin to the point having the vector positionj i r 32-=m, the work down by this force is .(b) If its speed at the origin is 4.00 m/s, the speed of the particle at r is . 4l(c) The change in the potential energy of the system is .III) Calculate Following Problems:1. A 3.00-kg mass starts from rest and slides a distance ddown a frictionless 30.0° incline. While sliding, it comes intocontact with an unstressed spring of negligible mass, asshown. The mass slides an additional 0.200 m as it is broughtmomentarily to rest by compression of the spring (k=400N/m). Find the initial separation d between the mass and thespring.2. Two masses are connected by a light string passing over alight frictionless pulley as shown. The 5.00-kg mass is released fromrest.(a) Determine the speed of the 3.00-kg mass just as the 5.00-kg masshits the ground.(b) Find the maximum height to which the 3.00-kg mass rises.Chapter 5 Angular momentum and Rigid bodyI) Choose one correct answer among following choices1. A particle moves with position given by j i t r 43+=, where r is measured in meters when t is measured in seconds. For each of the following, consider only t > 0. The magnitude of the angular momentum of this particle about the origin isA. increasing in time.B. constant in time.C. decreasing in time.D. undefined2. A solid object is rotating freely without experiencing any external torques. In this caseA. Both the angular momentum and angular velocity have constant direction.B. The direction of angular momentum is constant but the direction of the angular velocity might not be constant.C. The direction of angular velocity is constant but the direction of the angular momentum might not be constant.D. Neither the angular momentum nor the angular velocity necessarily has a constant direction.3. A 2.0-kg block travels around a 0.50-m radius circle with an angular velocity of 12 rad/s. The magnitude of its angular momentum about the center of the circle is:A. 6.0kg · m 2/sB. 12 kg · m 2/sC. 48 kg/m 2 · sD. 72 kg · m 2/s 24. A 6.0-kg particle moves to the right at 4.0m/s as shown. Themagnitude of its angular momentum about the point O is:A. zeroB. 288 kg·m 2/sC. 144 kg·m 2/sD.24kg·m 2/s5. Two objects are moving in the x, y plane as shown.The magnitude of their total angular momentum (aboutthe origin O) is:A. zeroB. 6kg · m2/sC. 12kg · m2/sD. 30kg · m2/s6. A 2.0-kg block starts from rest on the positive x axis 3.0m from the origin and thereafter has a constant acceleration given by )/(342s m j i a-=. At the end of 2s its angular momentum about the origin is:A. 0B. (−36 kg·m 2/s)kC. (+48 kg·m 2/s)kD. (−96 kg·m 2/s)k7. As a 2.0-kg block travels around a 0.50-m radius circle it has an angular speed of 12rad/s. The circle is parallel to the xy plane and is centered on the z axis, a distance of 0.75m from the origin. The z component of the angular momentum around the origin is: A. 6.0kg · m 2/s B. 9.0kg · m 2/s C. 11kg · m 2/s D. 14kg · m 2/sII) Fill in the empty space with correct answer1. A particle located at the position vector )2(j i r-=m is acted by a force )3(j i F+=N . The torque about the origin should be_______m N ⋅.2. The velocity of a m =2kg body moving in the xy plane is given by )2(j i v-=m /s .Its position vector is )2(j i r+=m . Its angular momentum L about the origin should be___________s m kg 2⋅.3. Two particles each of mass m and speed v, travel in opposite directions along parallel lines separated by a distance d. The total angular momentum of the system about any origin is .4. A particle is located at r= (0.5m)i+ (−0.3m)j+ (0.8m)k. A constant force of magnitude 2N acts on the particle. When the force acts in the positive x direction, the components of the torque about the origin is , and when the force acts in the negative x direction, the components of the torque about the origin is .5. A uniform beam of length l is in a vertical position with its lower end on a rough surface that prevents this end from slipping. The beam topples. At the instant before impact with the floor, the angular speed of the beam about its fixed end is .6. A disk of mass m and radius R is free to turn about a fixed, horizontal axle. The disk has an ideal string wrapped around its periphery from which another mass m (equal to the mass of the disk) is suspended, as indicated in Figure. The magnitude of the acceleration of the falling mass is , the magnitude of the angular acceleration of the disk is .III) Calculate Following Problems:1. The pulley has radius 0.160m and moment of inertia 0.480kg ·m2. The rope does not slip on the pulley rim. Use energy methods to calculate the speed of the 4.00-kg block just before it strikes the floor.2. A block with mass m slides down a surface inclined 30to the horizontal . The coefficient of kinetic friction is μ. A string attached to the block is wrapped around a wheel on a fixed axis. The wheel has mass m and radius R with respect to the axis of rotation. The string pulls without slipping .a) What is the acceleration of the block down the plane?b) What is the tension in the string?3. A wooden block of mass M resting on a frictionless horizontal surface is attached to a rigid rod of length l and of negligible mass. The rod is pivoted at the other end. A bullet of mass m traveling parallel to the horizontal surface and normal to the rod with speed v hits the block and becomes embedded in it. What is the angular momentum of the bullet –block system?Chapter 9 Mechanic oscillationI) Choose one correct answer among following choices1. A particle on a spring executes simple harmonic motion. If the mass of the particle and the amplitude are both doubled then the period of oscillation will change by a factor ofA. 4.B. 8.C. 2.D. 2 2. A particle is in simple harmonic motion with amplitude A. At time t=0 it is at x=-A/2 and is moving in the negative direction, then the initial phase is:A. 2π/3 radB. 4π/3 radC. π radD. 3π/2 rad3. A particle is in simple harmonic motion with period T. At time t = 0 it is at the equilibrium point. Of the following times, at which time is it furthest from the equilibrium point?A. 0.5TB. 0.7TC. TD. 1.4T4. A weight suspended from an ideal spring oscillates up and down with a period T. If the amplitude of the oscillation is doubled, the period will be:A. TB. 2TC. T/2D. 4T5. The displacement of an object oscillating on a spring is given by x(t) = A cos(ωt + φ). If the initial displacement is zero and the initial velocity is in the negative x direction, then the phase constant φ is:A. 0B. π/2 radC. π radD. 3π/2 rad6. An object is undergoing simple harmonic motion with period T, amplitude A and initial phase πϕ31-=. Its graph of x versus t is:7. An object of mass m, oscillating on the end of a spring with spring constant k , has amplitude A. Its maximum speed is:A. m k A /B.m k A /2C. k m A /D. k Am /II) Fill in the empty space with correct answer1. The total energy of a simple harmonic oscillator (谐振子) with amplitude A and force constant k is_________.2. Find the initial phases (初相) of the simple harmonic motion as shown in figure.1ϕ= 2ϕ=III) Calculate Following Problems:1. An object oscillates with simple harmonic motion along the x axis. Its displacement from the origin varies with time according to the equation: )4cos()00.4(ππ+=t m x .where t is in seconds and the angles in the parentheses are in radians.－－1/21/2A －1/21/2A A －1/21/2A A －1/21/2A A。

【导语】很多⼈在学习的过程中认为英语最难的就是⼝语学习，其实要想提⾼⾃⼰的英语⼝语能⼒，平时⼀定要养成多开⼝，多联系的好习惯，英语的学习在于长期的积累。

以下是整理的⼯程英语⼝语的常⽤句⼦，欢迎阅读！1.⼯程英语⼝语的常⽤句⼦ 1、The design of the process piping is performed directly on a model of the project. ⼯艺配管的设计是直接按照⼯程项⽬的⼀个模型完成的。

2、The model is an actual working tool for piping. 模型是配管⽤的实际⼯具。

3、Piping erection work include: prefabrication, placing, aligning, welding and bolting. 管道安装⼯作包括：预制加⼯、安置、对准、焊接和连接。

4、We can perform the pipe by following operations: cutting and mechanical chamfering, manual and automatic welding. 我们可以对管⼦进⾏下列预制加⼯：切割和机械加⼯坡⼝,⼿⼯和⾃动焊接等。

5、The computer generates isometric drawings and prints out bill of materials. 计算机绘出管道空视图,并打印出材料明细表。

6、Seamless steel tube is made in sizes for 1/8 to 24 inches. ⽆缝钢管制作的尺⼨从⼋分之⼀⼨到⼆⼗四⼨。

7、Spiral-welded steel pipe is available in sizes from 6 to 36 inches. 螺旋焊接钢管的尺⼨从六⼨到三⼗六⼨。

Peter Pan（小飞侠彼得·潘）J.M.BarrieContents1.The Darling family2.Peter loses his shadow3.Wendy helps Peter4.The children learn to fly5.Neverland6.Poor Wendy!7.The boys build a house8.Wendy’s story9.The pirates attack10.Tinker Bell saves Peter’s life11.On the Jolly Roger12.Back home13.The Lost Boys find a mother14.And so it continues for ever and ever! Page6About the AuthorJames Matthew Barrie was born in1860 in Angus,Scotland.He is the ninth of ten children and his parents are weavers.As a child he loves reading and playing make-believe games about pirates with his school friends.Barrie grows up in Scotland, then he moves to London because he wants to become a writer.He writes novels,plays for the theatre and articles for newspapers.He also makes friends with many writers.In London,Barrie often takes his dog for walks in Kensingston Gardens.One day he meets the Llewelyn Davies family there: George,John,Michael,Peter and Nicholas, and their mother,Sylvia.They become good friends and Barrie starts to spend a lot of time with the family.He invents stories to entertain the boys.He tells them that baby Peter can fly, and the bars on the windows of the children's bedroom are to stop him flying away.The idea for the story of Peter Pan is born.First Barrie writes a play called Peter Pan.It is very popular and he decides to write a novel.目录1.可爱的家庭2.彼得失去了他的影子3.温迪帮助彼得4.孩子们学习飞行5.梦幻岛6.可怜的温迪!7.男孩们盖了一座房子8.温迪的故事9.海盗袭击10.小叮当救了彼得的命11.在海盗船上12.回家13.失落的男孩找到了一位母亲14.这样下去，直到永远、永远!第6页关于作者1860年，詹姆斯·马修·巴里出生于苏格兰的安格斯。

Maths Chapter 6 Squares and Square Roots with Answers 数学第六章平方和平方根1. The Pythagorean triples whose smallest number is 8:1.毕达哥拉斯的最小数字为8的三元组：a) 8, 16 17 b) 8, 17, 18 c) 8, 15, 17 d) 8, 15, 16 Answer/Explanation 回答/解释Answer: (c) Explanation: The general form of Pythagorean triplets is 2m, m2-1, m2+1答：（c）说明：毕达哥拉斯三胞胎的一般形式是2m，m2-1，m2+1So, m = 4所以，m=4m2–1=42-1=16-1=15m2+1=42+1=16+1=172. Which of the following is a perfect square?2.下列哪一项是完全平方？a) 1057 b) 625 c) 7928 d) 64000Answer/Explanation 回答/解释Answer: (b) Explanation: The natural numbers which end with 0,2,3,7 and 8 are not perfect squares. Hence, 625 is a perfect square.答：（b）说明：以0、2、3、7、8结尾的自然数不是完全平方。

因此，625是一个完全的平方数。

25 x 25 = 6253. Which of the following will have 6 at unit place?3.以下哪一项在个位有6个？a) 192 b) 112 c) 242 d) 132Answer/Explanation 回答/解释Answer: (c) Explanation: 242= 24 x 24 = 576回答：（c）说明：242=24 x 24=5764. If 5278 is squared, then what will be at unit place?4.如果5278平方后，那个位是多少？a) 8 b) 7 c) 6 d) 4Answer/Explanation 回答/解释Answer: (d) Explanation: If we square the unit digit of the number 5278 we get:回答：（d）说明：如果我们把数字5278的个位数字平方，我们得到：82 = 64Hence, at the unit place of 52782 the number is 4.因此，52782的个位数数字是4。

【导语】在⽇常英语学习的过程中，⼤家不仅要掌握单词语法，还要多听、多看、多说和多练，这样才能够达到真正的学习⽬的。

以下是整理的校园中常⽤英语⼝语句⼦，欢迎阅读！1.校园中常⽤英语⼝语句⼦ 1. that’s all(so much) for the class .time’s up.下课时间已到，本课时就讲这么多。

2. after class,you’re to read the text again.课后，⼤家还得再读⼀会⼉。

3. and you ought to hand in the homework in time.⼤家要及时上交作业。

4. let’s take a break, see you later,everyone.休息⼀会⼉，同学们，再见。

5. according to the study demand (require) and our arrangement,we’ll do an action.根据学习需要和安排，我们要搞⼀项活动。

6. from now on, at the beginning of every chinese class, we’ll ask someone to do the oral composition.从现在开始，在每堂语⽂课上课之始，我们请同学们做⼝头作⽂。

7. do you understand what i said just now ?⼤家明⽩我刚才说的意思吗? 8. now, you may make preparations for it in ten minutes.现在，⼤家可以准备⼗分钟。

9. the lecture will begin in a minute, let’s get ready.演讲稍候就要开始，准备⼀下。

2.学习⽇常英语⼝语的⽅法 1、学习⽇常英语⼝语时，学⽣⾸先需要背过和掌握最基本的单词词汇，之后可以通过⼀些课⽂或者英语⼩⽂章的学习来背诵⼀些⽇常对话的句⼦，以作储备。

Peter Pan （小飞侠彼得·潘）J. M. BarrieContents1. The Darling family2. Peter loses his shadow3. Wendy helps Peter4. The children learn to fly5. Neverland6. Poor Wendy!7. The boys build a house8. Wendy’s story9. The pirates attack10. Tinker Bell saves Peter’s life11. On the Jolly Roger12. Back home13. The Lost Boys find a mother14. And so it continues for ever and ever!Page 6About the AuthorJames Matthew Barrie was born in 1860 in Angus, Scotland. He is the ninth of ten children and his parents are weavers. As a child he loves reading and playing make-believe games about pirates with his school friends. Barrie grows up in Scotland, then he moves to London because he wants to become a writer. He writes novels, plays for the theatre and articles for newspapers. He also makes friends with many writers.In London, Barrie often takes his dog for walks in Kensingston Gardens. One day he meets the Llewelyn Davies family there: George, John, Michael, Peter and Nicholas, and their mother, Sylvia. They become good friends and Barrie starts to spend a lot of time with the family. He invents stories to entertain the boys. He tells them that baby Peter can fly, and the bars on the windows of the children's bedroom are to stop him flying away. The idea for the story of Peter Pan is born. First Barrie writes a play called Peter Pan. It is very popular and he decides to write a novel.目录1. 可爱的家庭2. 彼得失去了他的影子3. 温迪帮助彼得4. 孩子们学习飞行5. 梦幻岛6. 可怜的温迪!7. 男孩们盖了一座房子8. 温迪的故事9. 海盗袭击10. 小叮当救了彼得的命11. 在海盗船上12. 回家13. 失落的男孩找到了一位母亲14. 这样下去，直到永远、永远!第6页关于作者1860年，詹姆斯·马修·巴里出生于苏格兰的安格斯。

Worksheet on Significant Figures有效数字练习题Take the guidance on the concept of Significant Figures by taking the help of Worksheet on Significant Figures. Practice all the problems present in the Significant Figures Worksheets and get a good grip on the topic. Test your subject knowledge by taking the practice tests available in the document. Also, you can easily enhance your problem-solving skills by solving Worksheet on Significant Figures on a daily basis. Assess your preparation standards and concentrate on the areas you are facing difficulty.借助有效数字练习题，对有效数字概念进行指导。

练习重要数字练习题中的所有问题，并掌握好这个主题。

通过文档里的提供的实践测试可以测试你的掌握程度。

此外，你可以轻松地提高你解决问题的能力，你可以每天练习。

评估你的标准，集中精力在你觉得困难的领域。

Significant Figures Examples with Answers重要数字题目示例（附答案）Check different problems impose on Significant Figures and get a grip on every concept available in the Significant Figures.检查对有效数字所问的不同问题，掌握有效数字中可用的每个概念。

练习双语：看英国父母怎么给孩子取名字父母给孩子取什么样的名字，可能寄托了他们对孩子的期望。

那么，你会给孩子取家具名吗？英国“宝宝中心〃网站推荐了一些宜家公司家具的名称，或许将引领今年英国婴儿取名流行趋势。

The year has already seen baby-name trends galore, with gender-neutral monikers reigning supreme.今年给宝宝取名的各种趋势花样纷呈，中性名字大行其道。

And Baby Centre has now earmarked names inspired by lkea as a potential new trend to sweep the nation.〃宝宝中心〃日前发布了受宜家家居启发而取的宝宝名，据称这将成为在英国流行的新趋势。

The furniture manufacturer often chooses traditional Scandinavian names for its products with the Billy bookcase, Malm bed and Tarva wooden range among its most popular lines.宜家公司常选择传统斯堪的纳维亚名字给产品命名，最受欢迎的产品有比利书架、马尔姆床和塔尔瓦实木家具系列等等。

Writer Lucy BC suggests: 'Naming your baby after IKEA furniture might seem ridiculous at first glance, but don't dismiss the idea!作者露西-BC建议说：〃给孩子取宜家家具名第一眼看似有点滑稽，不过不要拒绝这个想法。

〃,IKEA is known for the charming Scandinavian names it gives its products and many work surprisingly well as baby names."〃我们都知道，宜家用美丽的斯堪的纳维亚名字为产品命名，其中很多也非常适合做宝宝名。