The Effects of Dexmedetomidine on Cardiac Electrophysiology in Children
Gregory B.Hammer,MD*?David R.Drover,MD*
Hong Cao,MD*
Ethan Jackson,MD* Glyn D.Williams,MB,ChB* Chandra Ramamoorthy,
MBBCHir* George F.Van Hare,MD?
Alisa Niksch,MD?Anne M.Dubin,MD?BACKGROUND:Dexmedetomidine(DEX)is an?
2
-adrenergic agonist that is approved by the Food and Drug Administration for short-term(?24h)sedation in adults.It is not approved for use in children.Nevertheless,the use of DEX for sedation and anesthesia in infants and children appears to be increasing.There are some concerns regarding the hemodynamic effects of the drug,including bradycardia, hypertension,and hypotension.No data regarding the effects of DEX on the cardiac conduction system are available.We therefore aimed to characterize the effects of DEX on cardiac conduction in pediatric patients.
METHODS:Twelve children between the ages of5and17yr undergoing electrophysi-ology study and ablation of supraventricular accessory pathways had hemody-namic and cardiac electrophysiologic variables measured before and during administration of DEX(1?g/kg IV over10min followed by a10-min continuous infusion of0.7?g?kg?1?h?1).
RESULTS:Heart rate decreased while arterial blood pressure increased significantly after DEX administration.Sinus node function was significantly affected,as evidenced by an increase in sinus cycle length and sinus node recovery time. Atrioventricular nodal function was also depressed,as evidenced by Wenckeback cycle length prolongation and prolongation of PR interval.
CONCLUSION:DEX significantly depressed sinus and atrioventricular nodal function in pediatric patients.Heart rate decreased and arterial blood pressure increased during administration of DEX.The use of DEX may not be desirable during electrophysiology study and may be associated with adverse effects in patients at risk for bradycardia or atrioventricular nodal block.
(Anesth Analg2008;106:79–83)
D exmedetomidine(DEX)is a highly selective?2-
adrenergic agonist that is approved by the Food and Drug Administration for short-term(?24h)sedation in adult patients in the intensive care unit.It is not approved for use in children1;however,the use of DEX in infants and children for sedation and analgesia in the pediatric intensive care unit has been re-ported.2–4In addition,there are a growing number of published reports describing the administration of DEX during anesthesia in adults and children.5,6 There is concern regarding the circulatory effects of DEX,including hypertension,hypotension,and bra-dycardia.7It is thought that hypertension is due to activation of peripheral?2B-adrenergic receptors,lead-ing to vasoconstriction.8Hypertension may be a tran-sient,initial circulatory effect after an initial loading dose of DEX and may also be associated with continu-ous infusions resulting in high plasma concentra-tions.9Entry into the central nervous system(CNS) leads to activation of?2A-adrenergic receptors in the locus coeruleus,causing a decrease in norepinephrine release.10,11This CNS effect of DEX is associated with a decrease in arterial blood pressure(MAP).The decrease in heart rate(HR)associated with the adminis-tration of DEX may be caused both by a reflex response at the sinus node to peripheral vasoconstriction and the decrease in sympathetic outflow from the CNS.
At the cellular level,the interaction of DEX with ?2-adrenergic receptors results in activation of G pro-teins.12This leads to a decrease in adenylate cyclase activity.13The resulting decrease in the intracellular concentration of cyclic adenosine monophosphate causes an alteration in ion channel conductance and decreased neuronal activation.14,15This accounts for the clinical effects of DEX.It is unknown whether the cardiac effects of DEX are related strictly to interaction with?2A-adrenergic receptors in the CNS and?2B-adrenergic receptors in the peripheral vasculature,or whether direct interaction with?2-adrenergic recep-tors in the heart itself may play a role.
The aim of this study was to characterize the effects of DEX on cardiac conduction in children.
From the Departments of*Anesthesiology,and?Pediatrics, Lucile Packard Children’s Hospital and Stanford University School of Medicine,Stanford,California.
Accepted for publication September11,2007.
Reprints will not be available from the author.
Address correspondence to Gregory B.Hammer,MD,Department of Anesthesia,Stanford University Medical Center,300Pasteur Dr., Stanford,CA94305-5640.Address e-mail to ham@https://www.doczj.com/doc/867203138.html,.
Copyright?2007International Anesthesia Research Society DOI:10.1213/01.ane.0000297421.92857.4e
METHODS
After IRB approval and informed consent,12pa-
tients were included in this study.They were5–17yr
of age and scheduled for a cardiac electrophysiology
(EP)study and ablation under anesthesia for a diag-
nosis of supraventricular tachycardia(SVT).Patients
in whom ablation was attempted but not successful,as
well as those with atrioventricular(AV)nodal dys-
function,were excluded.Antiarrhythmic medications
were discontinued in all patients at least3days before
the procedure.
Patient monitoring included electrocardiogram
(ECG),noninvasive MAP,skin temperature,pulse
oximetry,and capnography.Supplemental oxygen
was administered via nasal cannula or facemask dur-
ing spontaneous breathing.Patients were premedi-
cated with midazolam(0.5mg/kg up to20mg PO or
1–2mg IV)as needed.Continuous infusions of propo-
fol75–125?g?kg?1?min?1IV and ketamine3.75–12.5?g?kg?1?min?1were administered to achieve an adequate level of sedation and analgesia for catheter
insertion and EP study and ablation.
Once stable anesthesia was achieved,the right
femoral vein and right internal jugular vein were cath-
eterized using standard techniques.Electrode catheters
were advanced to the right atrial appendage,right
ventricular apex,His Bundle location,and coronary
sinus.A diagnostic EP study was then performed using
a standard protocol.If SVT was not induced in the
baseline state,isoproterenol(0.01–0.04?g?kg?1?min?1) was added and the protocol repeated.Once the ar-rhythmia focus was identified,radiofrequency or cryoablation was performed.
After a30-min observation period to ensure the
success of the ablation and to allow offset of the
isoproterenol,baseline EP data were recorded.Base-
line surface ECG intervals,including PR,QRS,QT
interval corrected for rate using Bazett’s formula
(QTc),and sinus cycle length,were measured.Intra-
cardiac intervals,specifically atrial-His and His-
ventricular intervals,were measured.Sinus node
function was assessed by measuring corrected sinus
node recovery times using standard techniques,mea-
suring the return interval after30s of progressive
right atrial overdrive pacing cycle lengths until the
return interval did not further prolong.The maximum
recovery interval was corrected by subtracting the
sinus cycle length.AV nodal and atrial effective
refractory periods were also measured by introducing
progressively more premature atrial stimuli after
eight-beat atrially-paced drive trains at a set cycle
length.Ventriculoatrial block cycle length was mea-
sured with ventricular overdrive pacing.VA and
ventricular effective refractory periods were assessed
with placement of a ventricular extrastimulus after an
eight-beat paced drive train in the ventricle.
After recording of baseline EP data,DEX1?g/kg IV was administered over10min,followed by a continuous infusion at a dose of0.7?g?kg?1?h?1for 10min.The ECG and intracardiac electrograms were continuously recorded before and during this20-min infusion period.The identical EP data were again recorded after the20-min DEX infusion period in the same order as previously recorded before discontinu-ation of the drug.The EP study was terminated upon completion of this monitoring and data collection period.Indwelling catheters were removed,anesthet-ics were discontinued,and the patient was trans-ported to the postanesthesia care unit.Continuous observation of the ECG was performed in the postan-esthesia care unit until complete recovery from anes-thesia(i.e.,1–2h).Using study-specific flow sheets, nursing staff recorded vital signs every5min to document variations in HR and MAP.Any episodes of bradycardia and/or tachycardia(HR?or?95% confidence limits for age,respectively)were recorded. As per routine for EP studies at this institution, patients were discharged4–6h after completion of their procedure.
SPSS version15.0for Windows was used for statis-tical https://www.doczj.com/doc/867203138.html,parisons of hemodynamic and re-spiratory variables were made from baseline versus10 and20min after initiation of DEX infusion using one-way ANOVA with post hoc comparisons of indi-vidual means by Tukey’s HSD test.Two-sided paired Student’s t-test compared the EP variable measured in a baseline state and after the20-min infusion of DEX. All results are expressed as mean?sd.A P value of ?0.05was considered statistically significant.
RESULTS
Patients
Fifteen patients were enrolled.One patient was withdrawn due to unsuccessful ablation,and two patients were withdrawn due to unanticipated AV nodal dysfunction.Twelve patients(7females and5 males)with a median age of13yr(5–17yr)and a median weight of59.5kg(20–117kg)were studied. All patients studied underwent successful ablation. Seven of the12patients received isoproterenol during the EP study.
Hemodynamic and Respiratory Variables
A significant increase in MAP was seen compared with baseline(66.2?9.3mm Hg)at10min(78.5?8.9 mm Hg,P?0.006)but not at20min(71.3?9.1mm Hg)during administration of DEX(Table1).This was accompanied by a significant decrease in HR compared with baseline(94.3?19.8bpm)at10min(75.9?17.1 bpm,P?0.045)but not at20min(80.1?16.8bpm).
Respiratory rate and end-tidal carbon dioxide (ET co2)did not change with administration of DEX.
EP Variables
Sinus node function was significantly depressed after administration of DEX(Table2).Corrected sinus
node recovery times increased significantly from base-line.AV nodal function also showed depression after administration of DEX.AV nodal block cycle lengths and PR intervals significantly lengthened.Neither atrial nor ventricular muscle refractoriness changed significantly,although the change in ventricular effec-tive refractory period did approach statistical signifi-cance.QTc,a measure of ventricular repolarization that is influenced by autonomic input,also signifi-cantly increased,but no patient had an abnormally prolonged QTc(i.e.,QTc?445ms). DISCUSSION
We found that DEX significantly depressed sinus and AV nodal function in pediatric patients.Sinus node recovery times(a measure of sinus automaticity) and baseline sinus cycle lengths,which are markers of sinus nodal function,were both lengthened with ad-ministration of DEX.AV nodal function,as evidenced by Wenckebach cycle length and AV nodal effective refractory periods,were also lengthened significantly.His-Purkinje conduction and atrial and ventricular
muscle properties were not affected.These effects
might be related to a decrease in sympathetic outflow
from the CNS and/or reflex effects secondary to an
increase in systemic vascular resistance.The concomi-
tant decrease in HR and increase in MAP after the
initial10-min infusion of DEX,followed by the subse-
quent decrease in MAP and increase in HR during the
next10min might suggest a reflex phenomenon.DEX
did not have a direct effect on ventricular or atrial
refractoriness,at least at the standard pacing sites cho-
sen.No spontaneous AV nodal block was seen in these
patients with normal baseline AV nodal conduction.
No patient developed clinically significant brady-
cardia during this study.Our patients were otherwise
healthy children with SVT.The changes we observed
in sinus node and AV conduction might predispose
patients with selected comorbidities to significant bra-
dycardia.Such patients might include those having
undergone cardiac surgery with conduction abnor-
malities noted intraoperatively and/or suture lines in
proximity to cardiac conduction tissue(e.g.,repair of
ventricular septal defect,AV canal).Patients receiving
other medications that affect cardiac conduction(e.g.,
digoxin,?-blockers,antiarrhythmic drugs)might also be at enhanced risk of bradycardia related to DEX
infusion,although further studies are needed to con-
firm this.
The incidence of bradycardia associated with DEX
in adult patients is9%.16Although the bradycardia
observed in clinical practice is usually mild,sinus
arrest may occur.Peden et al.reported an episode of
sinus arrest in a patient who was lying quietly and
talking while receiving an initial loading dose of DEX
(0.675?g/kg over15min).17This required treatment with two doses of atropine0.6mg IV and a brief
period of cardiac massage.Mitigating factors,such as
the effect of other drugs or the vagal stimulus of
intubation,could not be implicated.Two additional
patients in this study had brief,self-limited periods of
sinus arrest during an initial loading dose of DEX(1?g/kg over15min).These events occurred during laryngoscopy and the coadministration of propofol
and alfentanil infusions.The authors of this study
recommended that all patients under40yr of age
receiving dexmedetomidine should be pretreated with
an anticholinergic drug.Significant bradycardias,in-
cluding sinus pauses of3s,related to DEX have been
reported in up to40%of adult patients in other
Table1.Hemodynamic Variables at Baseline and at the Completion of an Initial Loading Dose(10min)and Subsequent Infusion (20min)of Dexmedetomidine
Heart rate(bpm)Respiratory rate(bpm)Mean arterial blood
pressure(mm Hg)
ET co2
(mm Hg)
Baseline94.3?19.818.2?2.366.2?9.341.2?6.1 10min75.9?17.1*18.8?2.678.5?8.9?43.2?7.9 20min80.1?16.818.0?2.971.3?9.144.2?7.5 *P?0.006;?P?0.045.
Table2.Electrophysiologic Variables at Baseline and After a
20-min Infusion of Dexmedetomidine
Baseline DEX P
Surface ECG
intervals
SCL606?140ms788?165ms?0.01
PR144?19ms162?17ms?0.01
QRS76?11ms79?13ms NS
QTc394?9ms424?9ms?0.01
Sinus automaticity
CSNRT212?179ms293?180ms?0.01
Atrial muscle
properties
AERP207?31ms208?17ms NS
AV nodal
properties
AH interval73?14ms82?12ms?0.01
AVNBCL352?87ms436?105ms?0.01
AVNERP310?85ms360?88ms?0.02
VABCL372?111ms460?134ms?0.01
His Purkinje
properties
HV interval40?7ms40?6ms NS
Ventricular muscle
properties
VERP220?22ms230?19ms0.06
ECG?electrocardiogram;SCL?sinus cycle length;PR?PR interval;QRS?QRS duration;
QTC?corrected QT interval;CSNRT?corrected sinus node recovery time;AERP?atrial
effective refractory period;AH interval?atrial–His interval;AVNBCL?AV node block cycle
length;AVNERP?AV node effective refractory period;VABCL?ventriculo-atrial block cycle
length;HV interval?His-ventricular interval;VERP?ventricular effective refractory period.
studies.18–20Sinus arrest has occurred in a young, healthy volunteer3.5h after receiving DEX.21In a study of the effects of a single IM dose of DEX(2.5?g/kg)for premedication before surgery,a previously
healthy patient had an episode of bradycardia with a HR of35bpm before anesthetic induction requiring pharmacologic management.19
The incidence of bradycardia associated with the administration of DEX in infants and children is unknown.A recent article summarized the published reports of the use of DEX in more than800pediatric patients.22In general,these reports highlight the fa-vorable sedative and anxiolytic properties of the drug and the limited adverse effects on hemodynamic and respiratory function.Severe bradycardia(HR?50 bpm)was reported in an infant receiving both digoxin and DEX.7The bradycardia was temporally related to initiation of the DEX infusion and resolved1h after the infusion was discontinued.Bradycardia(HR?70 bpm)has also been reported in a2-mo-old infant receiving DEX0.7?g?kg?1?h?1after repair of a ventricular septal defect.4The bradycardia resolved20 min after discontinuing the infusion.This patient was part of a retrospective review of pediatric patients treated with DEX after cardiac or thoracic surgery.
The respiratory rate and ETco2did not change during the administration of DEX.This is consistent with previous reports that DEX administration is not associated with a relevant degree of respiratory depression.
Patients in this study were receiving propofol and ketamine infusions in addition to DEX.The effects of these medications on cardiac conduction are not well described.It is possible that the effects we observed would have been different in the absence of these drugs.Because of the need to provide sedation and analgesia to our patients before obtaining baseline EP data,the administration of anesthetics was required. No changes were made in the infusion rates of propo-fol or ketamine proximate to the initiation of or during the administration of DEX,and the cardiac effects observed were likely primarily or completely related to DEX.
CONCLUSION
Dexmedetomidine significantly depressed sinus and AV nodal function in pediatric patients.It did not have a direct effect on ventricular or atrial refractori-ness.No spontaneous AV nodal block was seen, although these patients all had normal baseline AV nodal conduction.DEX was associated with an in-crease in MAP commensurate with a decrease in HR. Accordingly,the conduction changes observed in this study might be related to a decrease in the CNS of sympathetic tone and/or reflex response to systemic vasoconstriction caused by DEX.
We recommend that DEX not be used to provide sedation for EP studies,as the effects we observed are likely to cause undesired and misleading measure-ments of cardiac conduction and might also interfere with the inducibility of some tachycardias.DEX should be used with caution in patients at risk for bradycardia and/or AV nodal dysfunction due to associated comorbidities.
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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