Received date:2011-05-09 收稿日期:2011-05-09
Foundation item:Fundamental Resear ch Funds for Central Un iversities(2010M S006);Specialized Res earch Fund for th e Doctoral Program
of H igher E ducation(20100142120091)
基金项目:中央高校基本科研业务基金资助项目(2010M S006);高等学校博士学科点专项科研基金资助项目(20100142120091) Biography:W ANG Yu nqi(1985-),male,borin in H eilong jiang Provin ce.M aster candidate.H is r esear ch areas cover s the piezoelectric ceram -ics and devices.Correspondent author:FAN Guifen (1974-),female,born in H ubei Province,PH.D,ass ociate professor.Her re -sarch areas cover s th e ferroelectric and piezoelectric ceramics and devices. 作者简介:王允祺(1985-),男,黑龙江哈尔滨人,硕士生,主要从事压电材料与器件的研究。通信作者:范桂芬(1974-),女,湖北蕲春人,副
教授,博士,主要从事铁电、压电陶瓷材料与器件的研究。
文章编号:1004
-2474(2011)04-0597-05Effects of ZnO Addition on the Sintering Temperature and Piezoelectric
Properties of PSN -PZT Ceramic
WANG Yunqi 1,2,FAN Guifen 1,2,LV Wenzhong 1,2
(1.Dept.of Electronic Science and T ech nology,H uazhong University of Sciencean d T echnology,Wuhan 430074,China;
2.Key Lab.of Functional M aterials For Electronic Information,M OE,H uazhong University of Science and T ech nology,Wuh an 430074,China)
Abstract:T he effects o f ZnO addit ion on t he sintering temper atur e and piezoelect ric pro per ties o f PSN -PZT ce -r amic modified by Ba and Fe w ere investig ated in this w ork,in o rder to decr ease the sint er ing temper ature o f PZT piezoelect ric ceramic.T he relat ionship between t he micro structur e and pro per ties was analyzed by means of XR D and SEM.T he XRD patterns show ed that all the cer amics ex hibited the tetr ago na l per ovskite structur e.T he piezoe -lect ric propert ies are pro moted when ZnO content is low er than 0.1wt.%.M eanw hile,the specimens w ith 0.1w t.%o f ZnO addition also exhibit ed ex cellent piezoelect ric pr operties.T hese results demonst rated that pro per ZnO additive could decr ease the sintering temper ature and enhance the piezoelectr ic pro per ties.
Key words:piezoelect ric ceramic;lo w temperatur e sinter ing;ZnO addit ion
ZnO 掺杂对PSN -PZT 陶瓷烧结温度及压电性能的影响
王允祺
1,2
,范桂芬1,2,吕文中
1,2
(1.华中科技大学电子科学与技术系,湖北武汉430074;
2.华中科技大学电子信息功能材料教育部重点实验室(B 类),湖北武汉430074)
摘 要:为了降低PZT 压电陶瓷的烧结温度,研究了ZnO 掺杂对Ba 、Fe 改性的P SN -PZT 陶瓷的烧结温度和压电特性的影响。通过XRD 和SEM 测试手段,分析了微观结构和材料性能的关系。XRD 结果显示所有样品均呈现四方钙钛矿结构。在w (ZnO)<0.1%时陶瓷压电性能随Z nO 的增加而提高;当w (ZnO)=0.1%时,陶瓷样品同样展现出了优良的压电性能。这些结果证明了适量的ZnO 掺杂可以降低陶瓷的烧结温度并提高压电性能。
关键词:压电陶瓷;低温烧结;ZnO 掺杂中图分类号:T M 282 文献标识码:A
0 Int roduction
The PZT ceramics are w idely used in various electr onic devices for their ex cellent piezoelectric and dielectric properties.With the development o f
micro -electronics,the m ultilayer ceramic devices have receiv ed considerable attention because o f the w ide rang e o f their applicatio ns
[1]
.The sintering
temperature o f ceram ics is needed to be low er to enable the use o f cheaper electr odes.Consequent -ly,extensive research w orks have been carr ied out
to decrease the sintering temperature o f the m ater-i al such as using advanced sintering technolog y and chemical doping.The advanced technolo gies such as ho t pressing require expensive equipm ents and the pr oduction v olume is limited.By contr ast,the
第33卷第4期压 电 与 声 光
Vo l.33No.42011年8月
PIEZO EL ECT RI CS &ACO U ST OO PT ICS
A ug.2011
chemical doping is much cheaper.H ence,m any re-searchers have reported PZT-based piezoelectric ce-r am ics w ith low sintering temperature by using low-melting point m etal ox ide additiv es as sintering aid,including ZnO,CuO,Li2CO3,LiBiO2, Pb5Ge3O11,BiFeO3,etc[2-4].On the other hand,low-temperature sintering can also be realized by using glass additives,such as B-B-i Cd glass,Pb-T-i Zr-S-i Bi glass etc[5-6].
In the various types o f multilayer piezoelectric devices,piezoelectric m otors have been ex tensiv e studied for the applications in m icro-mechanics and micro-electronics.In o rder to improve the displace-m ent and decrease the response time of the piezoe-lectr ic motors,the ceramics should possess a hig h electr omechanical coupling coefficient,lo w mechan-ical quality factor and low sintering tem perature.
H ow ev er,it is found that the piezo electric ceram-ics w ith such proper ties are seldom r eported. PbSb1/2N b1/2O3-PZT(PSN-PZT)ceramic mo dified by Ba and Fe is an ex cellent soft piezo electric mate-r ial w hich exhibits hig h electrom echanical coupling coefficient and low m echanical quality factor,but its sintering temperature is hig her than1200e.In this paper,the effect of ZnO additio n on the sinte-r ing tem perature and piezoelectric properties o f PSN-PZT ceramics modified by Ba and Fe w as in-v estig ated.
1Experimental Procedure
The ceram ics with compositions o f Pb0.97Ba0.03 [(Sb0.75Fe0.25)0.5Nb0.5]0.02(Zr0.51T i0.47)O3(PBFSN-PZT)+x w t.%o f ZnO w er e prepared by a conven-tional mix ed ox ide process,w her e x w as0.05, 0.10,0.20,0.30.T he reag ent grade raw po w ders of Pb3O4,ZrO2,T iO2,Sb2O3,Nb2O5,Fe2O3,Ba-CO3,ZnO w ere used as starting m aterials.T hese pow der s w ere mixed by ball milling for3h,using zirco nia ball and deionized w ater.After ball mil-l ing,the m ixture w as dr ied and subsequently ca-l cined at850e for2h.T he calcined pow der w as then ball milled again for3h.A fter dry ing,pow-der s were added with5w t.%of PVA solution for g ranulatio n,and then w ere pr essed into plates w ith dimensions of40mm@10mm@1mm.The pellets w ere sintered at1150e fo r3h.The elec-trodes w ere made by painting w ith silver paste and firing at550e for10min.T he sam ples w ere po led at120e in silicon o il bath by applying a DC elec-tric field of4kV/mm for15m in.T he piezo electric proper ties w ere m easured after24h o f ag ing at ro om temperature.
T he piezo electr ic constant d33w as measur ed using a quas-i static d33meter(ZJ-3A,China).The electrom echanical co upling coefficience kp and the electrom echanical quality factor Q m w ere calculated from the resonance and antireso nance fr equencies using precise im pedance analyzer(H P4192,Ang-i lent).The phase structure of the samples w as ana-lyzed by X-ray diffraction analysis(Rigaku Dmax-rC,Japan).T he fractured surfaces w ere ex amined by scanning electron micr oscopy(FEI-Sirion2000, Philip,N ether land).T he ferroelectric pro perties w ere examined using a fer roelectric testing sy stem (ZX-1).T he dielectric pro perties w ere measured by a capacitance meter(T H2613).The temperature dependence o f the dielectric constant w as measur ed by the capacitance meter and an auto matic temper-ature controller.
2Result s and Discussions
Fig.1show s the XRD patterns of PBFSN-PZT ceram ics added w ith various ZnO concentratio ns and sintered at1150e for3h.All the specimens appear a complete single phase with tetra gonal per ovskite phase,and no secondary phase is detec -
Fig.1XRD patter ns o f PBFSN-PZT cer amics added w ith v arious ZnO co ncentrat ions sinter ed at1150e
598压电与声光2011年
ted.Fig.2show s the ratio of lattice co nstant c and
a w ith various ZnO concentrations.T he m ax imum value of c /a is obtained for the specimens w ith x =0.10.These r esults r eflect that the anisotro py o f specimens increases w ith ZnO content low er than 0.1w t.%,and then decreases w hen ZnO content is over 0.1w t.
%.
Fig.2 V alues o f c /a o f PBFSN -PZT cer amics added w ith
var ious ZnO concentr atio ns sintered at 1150e
Fig.3sho w s SEM microgr aphs o f PBFSN -PZT ceramics w ith different ZnO concentr ations
and sintered at v ar io us tem peratures.In Fig.3(a),the g rain size o f the sam ples is about 5L m,and in -creases up to 10L m w ith x =0.1,as sho w n in Fig.3(b).In Fig.3(c),it can be fo und that the g rain size decreases to 2L m.T he increase of g rain size is attributed to the effect o f ZnO on the improvement of the sinter ability.When ZnO concentration is over 0.1w t.%,the ex cess ZnO additiv e ex ists in
F ig.3 SEM microg raphs of PBFSN -PZT cer amics with
different ZnO concentr ations
the g rain boundary,w hich prevents the gr ain g row th during sintering ,so that the gr ain size of specimens decreases visibly.Fig.3(d)show s the SEM micro -structur e of ceramics sintered at 1050e w hen ZnO content is 0.1w t.%.Co mpar ed it w ith Fig.3(b),it can be observed that the gr ain size reduces and the amount of pores inside the ce -ramic increases with the decrease of sintering tem -perature.
Fig.4show s the density of the PBFSN -PZT ceram ics w ith various ZnO contents sinter ed at 1150e for 3h.The maxim um v alue of density 8.3628g /cm 3is obtained w hen ZnO content is 0.2w t.%.The increase of density w hen x is below 0.2dem onstrates that proper ZnO additio n can im -prove the sinter ability of the cer am
ics.
F ig.4 D ensity of the PBFSN -PZT ceramics w ith var ious
Z nO concentrat ions sint ered at 1150e
Fig.5show s the hysteresis loo ps of PBFSN -PZT ceramics w ith different ZnO content sinter ed at 1150e .It can be o bser ved that the v alue of P r decreases visibly w hen ZnO co ntent
is o ver
0.1w t%.Fro m the results of XRD,the aniso tr opy of the ceram ics im pro ves w hen ZnO concentr ation is low er than 0.1w t.%.With the im pro vement of the anisotropy ,the spontaneo us polarization of the ceram ics impr oves,w hile the amount of domains reorientated under electric field decreases.Conse -quently,the P r value of the mater ial keeps steadily.When the ZnO co ntent is ov er 0.1w t.%,the an-i so tr opy of the ceram ics dro ps w ith ZnO addition (Fig.2),w hich results in the decrease of the spon -
taneous polarization of the ceramics.H ence,the P r of ceramics decr eases visibly as ZnO co ntent is
第4期王允祺等:ZnO 掺杂对PSN -P ZT 陶瓷烧结温度及压电性能的影响599
abov e 0.1w t.%.On the other hand,increasing ZnO addition also reduces the coercive field of the
ceramics.
F ig.5 Hy steresis lo ops of the PBFSN -PZT cer amics wit h
var ious ZnO concentr atio ns sintered at 1150e
Fig.6show s the temperature dependence o f the dielectric permittiv ity for PBFSN -PZT ceram ics w ith v ar io us ZnO concentrations sinter ed at 1150e .With the increasing of ZnO additive,the Curie po int dro ps w hen ZnO content is less than 0.1w t.%.When ZnO additiv e is over 0.1w t.%,the Curie po int increases.The results r eflect that small co ncentratio n of ZnO addition can reduce the stability of spontaneous polarization.T he m elting point of the ZnO (1975e )is hig her than that o f TiO 2(1850e ).It m eans that the cohesion energ y of the Ti )O bo nd is low er than that of Zn )O bo nd,so that when ZnO co ntent is o ver 0.1w t.%,the Curie point of cer am ics impr oves w ith the in -crease of ZnO
content.
F ig.6 T emperature dependence o f the dielectric
per mittiv ity for PBF SN -PZT cer amics w ith different
ZnO co ntents sintered at 1150e
The dielectric per mittivity E
r and dielectric loss tan D of PBFSN -PZT cer am ics w ith different ZnO concentrations are show n in Fig.7.T he dielectric permittivity decreases w ith the incr ease of ZnO content.Generally,the variation of dielectric per -m ittivity is r elated to the rem nant polarization and the g rain size o f the ceramics.The rem nant polar-i
zation and gr ain size both decrease w hen ZnO add-i
tion is o ver 0.1w t.%.A s a r esult,the dielectric per mittivity decreases visibly w ith x =0.2.The m inimum v alue of dielectric loss is obtained w ith x =0.2,w hich is ow ing to the density gets the m ax imum value w ith 0.2w t.%of ZnO additive (Fig.
4).
Fig.7 Dielectric pro per ties of P BF SN -P ZT ceramics w ith
var ious ZnO content s sinter ed at 1150e
Fig.8show s the plots of the electrom echan-i
cal coupling facto r k 31,the mechanical quality facto r Q m and the piezo electric constant d 33of the cer am -ics w ith different contents o f ZnO sinter ed at 1150e .With the increase of ZnO contents,it can be ob -served that the max imum values o f d 33and k 31are obtained w hen the ZnO content is 0.1w t.%.The results demonstrate that pr oper ZnO additio n can improv e the piezoelectric properties and reduce the sintering temperatur e.T he m echanical quality fac -tor Q m is up to a minimum value w ith x =0.1,w hich is co rresponded w ith the tendency of d 33and k 31.The specimens w ith 0.1w t.%o f ZnO add-i
tion achieve the o ptical properties,w hich are as fo-l
low s:d 33=481pC/N,k 31=0.36,E r =1807.6,Q m =60.03,tan D =0.015
7.
Fig.8 P iezo electric pr operties of t he P BFSN -P ZT ceramics
w ith var ious ZnO contents sinter ed at 1150e
T he piezo electric and dielectr ic properties of PBFSN -PZT ceramics w ith various sintering tem -perature and ZnO contents are show n in Tab.1.
600压 电 与 声 光2011年
When ZnO content is0.1w t.%,it can be observed that the piezoelectric and dielectric properties de-crease w hen the sinter ing temperature dro ps.H ow-ever,compared w ith the samples sintered at 1150e w ithout any additive,the specim ens sin-tered at1050e w ith0.1w t.%of ZnO additio n show the sim ilar piezoelectric pro perties,and even the piezoelectr ic constant d33improves,w hich dem-o nstrates that pr oper ZnO addition reduces the sin-tering temper ature.
Tab.1Piezoelectric and dielectric pro perties o f
the PBFSN-PZT ceramics w ith various ZnO co ntents and sintering temperatures
Sintering temperature
ZnO
co ntent(w t.%)
d33/(pC/N)
1150e0423
1150e0.1481
1100e0.1467
1050e0.1437
k31Q m E r tan D
0.36858.662076.40.0167
0.36060.031807.60.0157
0.32358.471612.80.0160
0.35661.921611.70.0200
3Conclusions
The effects of ZnO on the sintering tempera-ture and piezoelectric proper ties of PSN-PZT ce-r am ics w ere inv estig ated.Fro m the XRD patterns of ceramics,it can be found that all the samples show the tetr ag onal perov skite structure.The an-i sotropy of cer am ics improv es w hen ZnO content is fro m0.05w t.%to0.1w t.%,and decreases w ith ZnO content over0.1w t.%.T he SEM micro struc-ture o f PBFSN-PZT cer am ics ex hibiting the m ax-i mum value o f the gr ain size is obtained w hen ZnO content is0.1w t.%.From the piezoelectric and d-i electric properties of PBFSN-PZT ceramics sin-ter ed at1150e,the optical proper ties are ob-tained w hen ZnO content is0.1w t.%,which are d33=481pC/N,k31=0.36,E r=1807.6,tan D= 0.0157,P r=24.5L C#cm-2,E c=16.3kV# cm-1,T C=368e.M eanw hile,the specim ens w ith 0.1w t.%ZnO addition also ex hibit an ex cellent p-i ezoelectric constant w hen sintered at a low er tem-perature1050e.T he results dem onstrate that proper ZnO additio n enhances the sinterability and reduces the sintering tem perature o f ceramics. References:
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第4期王允祺等:ZnO掺杂对PSN-P ZT陶瓷烧结温度及压电性能的影响601
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一般过去式 时间状语：yesterday just now (刚刚) the day before three days ag0 a week ago in 1880 last month last year 1. I was in the classroom yesterday. I was not in the classroom yesterday. Were you in the classroom yesterday. 2. They went to see the film the day before. Did they go to see the film the day before. They did go to see the film the day before. 3. The man beat his wife yesterday. The man didn’t beat his wife yesterday. 4. I was a high student three years ago. 5. She became a teacher in 2009. 6. They began to study english a week ago 7. My mother brought a book from Canada last year. 8.My parents build a house to me four years ago . 9.He was husband ago. She was a cooker last mouth. My father was in the Xinjiang half a year ago. 10.My grandfather was a famer six years ago. 11.He burned in 1991
●I wonder if it’s because I have been at school for so long that I’ve grown so crazy about going home. ●It is because she wasn’t well that she fell far behind her classmates this semester. ●I can well remember that there was a time when I took it for granted that friends should do everything for me. ●In order to make a difference to society, they spent almost all of their spare time in raising money for the charity. ●It’s no pleasure eating at school any longer because the food is not so tasty as that at home. ●He happened to be hit by a new idea when he was walking along the riverbank. ●I wonder if I can cope with stressful situations in life independently. ●It is because I take things for granted that I make so many mistakes. ●The treasure is so rare that a growing number of people are looking for it. ●He picks on the weak mn in order that we may pay attention to him. ●It’s no pleasure being disturbed whena I settle down to my work. ●I can well remember that when I was a child, I always made mistakes on purpose for fun. ●It’s no pleasure accompany her hanging out on the street on such a rainy day. ●I can well remember that there was a time when I threw my whole self into study in order to live up to my parents’ expectation and enter my dream university. ●I can well remember that she stuck with me all the time and helped me regain my confidence during my tough time five years ago. ●It is because he makes it a priority to study that he always gets good grades. ●I wonder if we should abandon this idea because there is no point in doing so. ●I wonder if it was because I ate ice-cream that I had an upset student this morning. ●It is because she refused to die that she became incredibly successful. ●She is so considerate that many of us turn to her for comfort. ●I can well remember that once I underestimated the power of words and hurt my friend. ●He works extremely hard in order to live up to his expectations. ●I happened to see a butterfly settle on the beautiful flower. ●It’s no pleasure making fun of others. ●It was the first time in the new semester that I had burned the midnight oil to study. ●It’s no pleasure taking everything into account when you long to have the relaxing life. ●I wonder if it was because he abandoned himself to despair that he was killed in a car accident when he was driving. ●Jack is always picking on younger children in order to show off his power. ●It is because he always burns the midnight oil that he oversleeps sometimes. ●I happened to find some pictures to do with my grandfather when I was going through the drawer. ●It was because I didn’t dare look at the failure face to face that I failed again. ●I tell my friend that failure is not scary in order that she can rebound from failure. ●I throw my whole self to study in order to pass the final exam. ●It was the first time that I had made a speech in public and enjoyed the thunder of applause. ●Alice happened to be on the street when a UFO landed right in front of her. ●It was the first time that I had kept myself open and talked sincerely with my parents. ●It was a beautiful sunny day. The weather was so comfortable that I settled myself into the
高中英语~词性~句子成分~语法构成 第一章节：英语句子中的词性 1.名词：n. 名词是指事物的名称，在句子中主要作主语.宾语.表语.同位语。 2.形容词;adj. 形容词是指对名词进行修饰~限定~描述~的成份，主要作定语.表语.。形容词在汉语中是（的）.其标志是: ous. Al .ful .ive。. 3.动词：vt. 动词是指主语发出的一个动作，一般用来作谓语。 4.副词：adv. 副词是指表示动作发生的地点. 时间. 条件. 方式. 原因. 目的. 结果.伴随让步. 一般用来修饰动词. 形容词。副词在汉语中是（地）.其标志是：ly。 5.代词：pron. 代词是指用来代替名词的词，名词所能担任的作用，代词也同样.代词主要用来作主语. 宾语. 表语. 同位语。 6.介词：prep.介词是指表示动词和名次关系的词，例如：in on at of about with for to。其特征：
介词后的动词要用—ing形式。介词加代词时，代词要用宾格。例如：give up her（him）这种形式是正确的，而give up she（he）这种形式是错误的。 7.冠词：冠词是指修饰名词，表名词泛指或特指。冠词有a an the 。 8.叹词：叹词表示一种语气。例如：OH. Ya 等 9.连词：连词是指连接两个并列的成分，这两个并列的成分可以是两个词也可以是两个句子。例如：and but or so 。 10.数词：数词是指表示数量关系词，一般分为基数词和序数词 第二章节：英语句子成分 主语：动作的发出者，一般放在动词前或句首。由名词. 代词. 数词. 不定时. 动名词. 或从句充当。 谓语：指主语发出来的动作，只能由动词充当，一般紧跟在主语后面。 宾语：指动作的承受着，一般由代词. 名词. 数词. 不定时. 动名词. 或从句充当. 介词后面的成分也叫介词宾语。 定语：只对名词起限定修饰的成分，一般由形容
M A: Has the case been closed yet? B: No, the magistrate still needs to decide the outcome. magistrate n.地方行政官，地方法官，治安官 A: I am unable to read the small print in the book. B: It seems you need to magnify it. magnify vt.１．放大，扩大；２．夸大，夸张 A: That was a terrible storm. B: Indeed, but it is too early to determine the magnitude of the damage. magnitude n.１．重要性，重大；２．巨大，广大 A: A young fair maiden like you shouldn’t be single. B: That is because I am a young fair independent maiden. maiden n.少女，年轻姑娘，未婚女子 a.首次的，初次的 A: You look majestic sitting on that high chair. B: Yes, I am pretending to be the king! majestic a.雄伟的，壮丽的，庄严的，高贵的 A: Please cook me dinner now. B: Yes, your majesty, I’m at your service. majesty n.１．［Ｍ－］陛下（对帝王，王后的尊称）；２．雄伟，壮丽，庄严 A: Doctor, I traveled to Africa and I think I caught malaria. B: Did you take any medicine as a precaution? malaria n.疟疾 A: I hate you! B: Why are you so full of malice? malice n.恶意，怨恨 A: I’m afraid that the test results have come back and your lump is malignant. B: That means it’s serious, doesn’t it, doctor? malignant a.１．恶性的，致命的；２．恶意的，恶毒的 A: I’m going shopping in the mall this afternoon, want to join me? B: No, thanks, I have plans already. mall n.（由许多商店组成的）购物中心 A: That child looks very unhealthy. B: Yes, he does not have enough to eat. He is suffering from malnutrition.
意见应以事实为根据. 3 来自辞典例句 192. The bombers swooped ( down ) onthe air base. 轰炸机 突袭 空军基地. 来自辞典例句 193. He mounted their engines on a rubber base. 他把他们的发动机装在一个橡胶垫座上. 14 来自辞典例句 194. The column stands on a narrow base. 柱子竖立在狭窄的地基上. 14 来自辞典例句 195. When one stretched it, it looked like grey flakes on the carvas base. 你要是把它摊直, 看上去就象好一些灰色的粉片落在帆布底子上. 18 来自辞典例句 196. Economic growth and human well - being depend on the natural resource base that supports all living systems. 经济增长和人类的福利依赖于支持所有生命系统的自然资源. 12 1 来自辞典例句 197. The base was just a smudge onthe untouched hundred - mile coast of Manila Bay. 那基地只是马尼拉湾一百英里长安然无恙的海岸线上一个硝烟滚滚的污点. 6 来自辞典例句 198. You can't base an operation on the presumption that miracles are going to happen. 你不能把行动计划建筑在可能出现奇迹的假想基础上.
英语造句大全English sentence 在句子中，更好的记忆单词！ 1、(1)、able adj. 能 句子：We are able to live under the sea in the future. (2)、ability n. 能力 句子：Most school care for children of different abilities. (3)、enable v. 使。。。能句子：This pass enables me to travel half-price on trains. 2、(1)、accurate adj. 精确的句子：We must have the accurate calculation. (2)、accurately adv. 精确地 句子：His calculation is accurately. 3、(1)、act v. 扮演 句子：He act the interesting character. （2）、actor n. 演员 句子：He was a famous actor. (3)、actress n. 女演员 句子：She was a famous actress. (4)、active adj. 积极的 句子：He is an active boy. 4、add v. 加 句子：He adds a little sugar in the milk. 5、advantage n. 优势 句子：His advantage is fight. 6、age 年龄n. 句子：His age is 15. 7、amusing 娱人的adj. 句子：This story is amusing. 8、angry 生气的adj. 句子：He is angry. 9、America 美国n.
主语+谓语 1. 理解主谓结构 1) The students arrived. The students arrived at the park. 2) They are listening. They are listening to the music. 3) The disaster happened. 2．体会状语的位置 1) Tom always works hard. 2) Sometimes I go to the park at weekends.. 3) The girl cries very often. 4) We seldom come here. The disaster happened to the poor family. 3. 多个状语的排列次序 1) He works. 2) He works hard. 3) He always works hard. 4) He always works hard in the company. 5) He always works hard in the company recently. 6) He always works hard in the company recently because he wants to get promoted. 4. 写作常用不及物动词 1. ache My head aches. I’m aching all over. 2. agree agree with sb. about sth. agree to do sth. 3. apologize to sb. for sth. 4. appear (at the meeting, on the screen) 5. arrive at / in 6. belong to 7. chat with sb. about sth. 8. come (to …) 9. cry 10. dance 11. depend on /upon 12. die 13. fall 14. go to … 15. graduate from 16. … happen 17. laugh 18. listen to... 19. live 20. rise 21. sit 22. smile 23. swim 24. stay (at home / in a hotel) 25. work 26. wait for 汉译英： 1.昨天我去了电影院。 2.我能用英语跟外国人自由交谈。 3.晚上7点我们到达了机场。 4.暑假就要到了。 5.现在很多老人独自居住。 6.老师同意了。 7.刚才发生了一场车祸。 8.课上我们应该认真听讲。9. 我们的态度很重要。 10. 能否成功取决于你的态度。 11. 能取得多大进步取决于你付出多少努力。 12. 这个木桶能盛多少水取决于最短的一块板子的长度。
【it's time to和it's time for】 ——————这其实是一个句型,只不过后面要跟不同的东西. ——————It's time to跟的是不定式（to do）.也就是说,要跟一个动词,意思是“到做某事的时候了”.如： It's time to go home. It's time to tell him the truth. ——————It's time for 跟的是名词.也就是说,不能跟动词.如： It's time for lunch.(没必要说It's time to have lunch) It's time for class.(没必要说It's time to begin the class.) They can't wait to see you Please ask liming to study tonight. Please ask liming not to play computer games tonight. Don’t make/let me to smoke I can hear/see you dance at the stage You had better go to bed early. You had better not watch tv It’s better to go to bed early It’s best to run in the morning I am enjoy running with music. With 表伴随听音乐 I already finish studying You should keep working. You should keep on studying English Keep calm and carry on 保持冷静继续前行二战开始前英国皇家政府制造的海报名字 I have to go on studying I feel like I am flying I have to stop playing computer games and stop to go home now I forget/remember to finish my homework. I forget/remember cleaning the classroom We keep/percent/stop him from eating more chips I prefer orange to apple I prefer to walk rather than run I used to sing when I was young What’s wrong with you There have nothing to do with you I am so busy studying You are too young to na?ve I am so tired that I have to go to bed early
《The Kite Runner》追风筝的人--------------------------------美句摘抄 1.I can still see Hassan up on that tree, sunlight flickering through the leaves on his almost perfectly round face, a face like a Chinese doll chiseled from hardwood: his flat, broad nose and slanting, narrow eyes like bamboo leaves, eyes that looked, depending on the light, gold, green even sapphire 翻译：我依然能记得哈桑坐在树上的样子，阳光穿过叶子，照着他那浑圆的脸庞。他的脸很像木头刻成的中国娃娃，鼻子大而扁平，双眼眯斜如同竹叶，在不同光线下会显现出金色、绿色，甚至是宝石蓝。 E.g.: A shadow of disquiet flickering over his face. 2.Never told that the mirror, like shooting walnuts at the neighbor's dog, was always my idea. 翻译：从来不提镜子、用胡桃射狗其实都是我的鬼主意。E.g.:His secret died with him, for he never told anyone. 3.We would sit across from each other on a pair of high
一、翻译 1. The idea of consciously seeking out a special title was new to me., but not without appeal. 让我自己挑选自己最喜欢的书籍这个有意思的想法真的对我具有吸引力。 2.I was plunged into the aching tragedy of the Holocaust, the extraordinary clash of good, represented by the one decent man, and evil. 我陷入到大屠杀悲剧的痛苦之中，一个体面的人所代表的善与恶的猛烈冲击之中。 3.I was astonished by the the great power a novel could contain. I lacked the vocabulary to translate my feelings into words. 我被这部小说所包含的巨大能量感到震惊。我无法用语言来表达我的感情（心情）。 4，make sth. long to short长话短说 5.I learned that summer that reading was not the innocent(简单的) pastime(消遣) I have assumed it to be., not a breezy, instantly forgettable escape in the hammock(吊床)，( though I’ ve enjoyed many of those too ). I discovered that a book, if it arrives at the right moment, in the proper season, will change the course of all that follows. 那年夏天，我懂得了读书不是我认为的简单的娱乐消遣，也不只是躺在吊床上，一阵风吹过就忘记的消遣。我发现如果在适宜的时间、合适的季节读一本书的话，他将能改变一个人以后的人生道路。 二、词组造句 1. on purpose 特意，故意 This is especially true here, and it was ~. (这一点在这里尤其准确，并且他是故意的) 2.think up 虚构，编造，想出 She has thought up a good idea. 她想出了一个好的主意。 His story was thought up. 他的故事是编出来的。 3. in the meantime 与此同时 助记：in advance 事前in the meantime 与此同时in place 适当地... In the meantime, what can you do? 在这期间您能做什么呢？ In the meantime, we may not know how it works, but we know that it works. 在此期间，我们不知道它是如何工作的，但我们知道，它的确在发挥作用。 4.as though 好像，仿佛 It sounds as though you enjoyed Great wall. 这听起来好像你喜欢长城。 5. plunge into 使陷入 He plunged the room into darkness by switching off the light. 他把灯一关，房
The effective sentences:(improve the sentences!) 1.She hopes to spend this holiday either in Shanghai or in Suzhou. 2.Showing/to show sincerity and to keep/keeping promises are the basic requirements of a real friend. 3.I want to know the space of this house and when it was built. I want to know how big this house is and when it was built. I want to know the space of this house and the building time of the house. 4.In the past ten years,Mr.Smith has been a waiter,a tour guide,and taught English. In the past ten years,Mr.Smith has been a waiter,a tour guide,and an English teacher. 5.They are sweeping the floor wearing masks. They are sweeping the floor by wearing masks. wearing masks,They are sweeping the floor. 6.the drivers are told to drive carefully on the radio. the drivers are told on the radio to drive carefully 7.I almost spent two hours on this exercises. I spent almost two hours on this exercises. 8.Checking carefully,a serious mistake was found in the design. Checking carefully,I found a serious mistake in the design.
M1 U1 一. 把下列短语填入每个句子的空白处（注意所填短语的形式变化）： add up (to) be concerned about go through set down a series of on purpose in order to according to get along with fall in love (with) join in have got to hide away face to face 1 We’ve chatted online for some time but we have never met ___________. 2 It is nearly 11 o’clock yet he is not back. His mother ____________ him. 3 The Lius ___________ hard times before liberation. 4 ____________ get a good mark I worked very hard before the exam. 5 I think the window was broken ___________ by someone. 6 You should ___________ the language points on the blackboard. They are useful. 7 They met at Tom’s party and later on ____________ with each other. 8 You can find ____________ English reading materials in the school library. 9 I am easy to be with and _____________my classmates pretty well. 10 They __________ in a small village so that they might not be found. 11 Which of the following statements is not right ____________ the above passage? 12 It’s getting dark. I ___________ be off now. 13 More than 1,000 workers ___________ the general strike last week. 14 All her earnings _____________ about 3,000 yuan per month. 二.用以下短语造句： 1.go through 2. no longer/ not… any longer 3. on purpose 4. calm… down 5. happen to 6. set down 7. wonder if 三. 翻译： 1.曾经有段时间，我对学习丧失了兴趣。（there was a time when…） 2. 这是我第一次和她交流。（It is/was the first time that …注意时态） 3.他昨天公园里遇到的是他的一个老朋友。（强调句） 4. 他是在知道真相之后才意识到错怪女儿了。（强调句） M 1 U 2 一. 把下列短语填入每个句子的空白处（注意所填短语的形式变化）： play a …role (in) because of come up such as even if play a …part (in) 1 Dujiangyan(都江堰) is still ___________in irrigation(灌溉) today. 2 That question ___________ at yesterday’s meeting. 3 Karl Marx could speak a few foreign languages, _________Russian and English. 4 You must ask for leave first __________ you have something very important. 5 The media _________ major ________ in influencing people’s opinion s. 6 _________ years of hard work she looked like a woman in her fifties. 二.用以下短语造句： 1.make (good/full) use of 2. play a(n) important role in 3. even if 4. believe it or not 5. such as 6. because of
English sentence 1、(1)、able adj. 能 句子：We are able to live under the sea in the future. (2)、ability n. 能力 句子：Most school care for children of different abilities. (3)、enable v. 使。。。能 句子：This pass enables me to travel half-price on trains. 2、(1)、accurate adj. 精确的 句子：We must have the accurate calculation. (2)、accurately adv. 精确地 句子：His calculation is accurately. 3、(1)、act v. 扮演 句子：He act the interesting character.（2）、actor n. 演员 句子：He was a famous actor. (3)、actress n. 女演员 句子：She was a famous actress. (4)、active adj. 积极的 句子：He is an active boy. 4、add v. 加 句子：He adds a little sugar in the milk. 5、advantage n. 优势 句子：His advantage is fight. 6、age 年龄n. 句子：His age is 15. 7、amusing 娱人的adj. 句子：This story is amusing. 8、angry 生气的adj. 句子：He is angry. 9、America 美国n. 句子：He is in America. 10、appear 出现v. He appears in this place. 11. artist 艺术家n. He is an artist. 12. attract 吸引 He attracts the dog. 13. Australia 澳大利亚 He is in Australia. 14.base 基地 She is in the base now. 15.basket 篮子 His basket is nice. 16.beautiful 美丽的 She is very beautiful. 17.begin 开始 He begins writing. 18.black 黑色的 He is black. 19.bright 明亮的 His eyes are bright. 20.good 好的 He is good at basketball. 21.British 英国人 He is British. 22.building 建造物 The building is highest in this city 23.busy 忙的 He is busy now. 24.calculate 计算 He calculates this test well. 25.Canada 加拿大 He borns in Canada. 26.care 照顾 He cared she yesterday. 27.certain 无疑的 They are certain to succeed. 28.change 改变 He changes the system. 29.chemical 化学药品