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3.單項(xiàng)選擇

1)     Only time will ________ if this agreement will bring a lasting peace.

A. speak  B. tell   C. say   D. talk

2)     The phone was ringing, but by the time she _________ indoors, it __________.

A. got; stopped   B. had got; stopped 

C. got; had stopped   D. had got; had stopped

3)     “I have to go,” she said, and with _______ she hung up the phone.

A. it  B. which  C. that   D. whom

4)     He bought the tickets ________ a friend at the stadium.

A. through   B. thorough   C. though   D. throughout

5)     Recycling saves energy, ________ acid rain, global warming and air pollution

A. so reduces   B. so reducing   C. thus reduces  D. thus reducing

6) --- ______ is it today?   --- It’s Tuesday.

  A. When   B. What time  C. What date   D. What day

7) Jack, together with his friends, _______ to climb out of the canyon.

A. decide   B. has decided   C. are to decide   D. are deciding

8) ______ exists music everywhere in our life! Shall we sing together?

  A. There   B. Where   C. Wherever   D. Therefore

9) The room, _________, is pleasant and airy. I love it very much.

  A. being small   B. it is small   C. but small   D. though small

10) Language are taught by the direct method, _________ , without using the students’ own language.

  A. believe it or not  B. to tell the truth  C. that’s to say   D. generally speaking

試題詳情

2.詞形變化

1)     Exercise is the ideal way to reduce _________ (tense) after a hard day.

2)     I’ll be ________ (thank) for a good night’s sleep after the busy week I’ve had.

3)     Many old people are living by ________ (them) and they fell lonely.

4)     He wrote a _________ (thrill), which told an exciting story about murder or crime.

5)     I’ve had such a _________ (tire) day. I just want to take a bath and go to bed.

6)     He works as a ___________ (translate) changes writing into a different language.

7)     It is ___________ (tradition) not to eat meant on Good Friday().

8)     We all had to go on a special ___________ (train) course to learn new sales techniques.

9)     As a seasoned (有經(jīng)驗(yàn)的) ___________ (travel), I know the value of being able to speak at lease a few words of the local language.

10)   He was __________ (terrify) at the thought of being trapped in the woods.

試題詳情

1.單詞拼寫

1)     Water boils at a t________________ of 100 degrees centigrade.

2)     The storm brought strong winds, t___________ and lightning.

3)     T________ is the dried brown leaves that are smoked in cigarettes.

4)     Every year we look for buried t___________ and we hope to find valuable things such as gold, silver and jewels.

5)     Gerry was born in China and his mother t_______________ is Chinese.

6)     She does some TV work, but t_________________ (戲劇)remains her first love.

7)     The teacher gave out copies of the new t_______________ (時(shí)間表) in the first class.

8)     Luke put out his hand and touched the t_____________ (微小的)fingers of the baby daughter.

9)     There’s a huge queue in the ladies’ t______________ (廁所).

10)   A lot of old t______________ (傳統(tǒng)) are dying out.

試題詳情

5.句子翻譯

1)   在學(xué)習(xí)方面爸爸對我要求很嚴(yán)格。(strict)

2)   他們成功找到了治療頭痛的方法。(succeed)

3)   爸爸的背不好。(suffer)

4)   這場演出不適合兒童觀看。(suitable)

5)   她在轉(zhuǎn)行進(jìn)入新聞業(yè)之前是一名圖書管理員。(switch)

6)   Ben向警察提供了那些涉案人員的姓名。(supply)

7)   我們強(qiáng)烈支持你的計(jì)劃。(support)

8)   這孩子在音樂方面有天賦。(talent)

9)   他把信撕成碎片,扔到垃圾箱里。(tear)

10) 他們談話的聲音很低,我聽不到他們說什么。(talk)

高三英語核心詞匯復(fù)習(xí)第24課時(shí)

(tell--- treat)

試題詳情

4.選詞填空

sweep   swear   success  straight   target   swing   swell  tease   task  strengthen

1)     The experiment was a big _________; the professor got what he wanted.

2)     The road was dead _______ and it had no bends at all.

3)     Our friendship has steadily ________ over the years.

4)     I didn’t mean to make you mad; I was only ____________.

5)     Ann had the ________ of preparing the agenda for meetings.

6)     I set myself a _________ of learning 20 new words a week. I hope I can achieves the goal.

7)     Let your arms ________ as you walk.

8)     Put some ice on your injured knee before it ________ up.

9)     Thunderstorms __________ the country and caused a huge loss.

10)   Dad _______ not to smoke again, but mum didn’t believe his promise.

試題詳情

3.單項(xiàng)選擇

1) --- What would you like?  --- Steak or chicken would _________.

  A. suit me fine   B. be fit   C. be suitable   D. be good

2) The ______ of this experiment were all men aged 18-35, and they were asked to write down how they felt during the test.

  A. students   B. subjects   C. surgeons   D. strangers

3) Suddenly an idea _______ me and I found it would be a perfect solution to our problem.

  A. submitted   B. struck   C. sucked   D. subscribed

4) They suggest ______ to a lawyer before I do anything.

  A. me talk   B. me to talk   C. my talking  D. I will talk

5) --- You said you’d have finished by today.  --- I said __________!

  A. not a such thing   B. such a not thing   C. such no thing  D. no such thing

6) The health expert ________ the importance of a balanced diet.

  A. stressed   B. strengthened   C. struggled   D. supported

7) The meeting _______ take place on Tuesday, but we’ve had to delay it.

  A. was subject to  B. was supposed to   C. was sure to   D. was suited to

8) Peter was suspected ______ government secrets to the enemy.

  A. to give off   B. of giving off   C. to give away  D. of giving away

9) As we all know, the dove is a ________ of peace.

  A. symbol   B. system   C. sign   D. symptom

10) Roger _____ painting for a while, but soon lost interest.

  A. took on   B. took in   C. took up   D. took over

試題詳情

2. 介詞填空

1)     All ______ a sudden, the lights went out.

2)     Your computer is far superior _______ mine.

3)     No one knows _______ sure what really happened.

4)     I have absolutely no sympathy _______ students who get caught cheating in exams.

5)     Were you successful ________ persuading him to change his mind?

6)     Millions of people are struggling __________ survival.

7)     Janet’s been __________ a lot of stress since her mother’s illness.

8)     Tom looked up ________ surprise as Dale walked in.

9)     The palace is surrounded _______ a high wall.

10)   Why don’t you come over ______ supper on Friday?

試題詳情

1.單詞拼寫

1) --- Where’s the station?  --- Sorry, I’m a s________ here myself.

2) Before choosing a career you should know your personal s________ and weaknesses.

3) The TV sex educational program is aimed at t____________, not adults.

4) Modern t_________ makes it possible for people to live longer than before.

5) Dead leaves floated on the s___________ of the water.

6) My possessions were a s_____________(衣箱) full of clothes and books.

7) A brief s_____________ (概要) is given on a separate sheet.

8) Tom is a regular customer in the s________________ (超市).

9) If you drink some water, it will make the pills easier to s_______________(吞咽).

10) These sausages are really t______________ (可口的). Where did you buy them?

試題詳情

數(shù)學(xué)教材是學(xué)習(xí)數(shù)學(xué)基礎(chǔ)知識、形成基本技能的“藍(lán)本”,能力是在知識傳授和學(xué)習(xí)過程中得到培養(yǎng)和發(fā)展的。新課程試卷中平面向量的有些問題與課本的例習(xí)題相同或相似,雖然只是個(gè)別小題,但它對學(xué)習(xí)具有指導(dǎo)意義,教學(xué)中重視教材的使用應(yīng)有不可估量的作用。因此,學(xué)習(xí)階段要在掌握教材的基礎(chǔ)上把各個(gè)局部知識按照一定的觀點(diǎn)和方法組織成整體,形成知識體系。

學(xué)習(xí)本章主要樹立數(shù)形轉(zhuǎn)化和結(jié)合的觀點(diǎn),以數(shù)代形,以形觀數(shù),用代數(shù)的運(yùn)算處理幾何問題,特別是處理向量的相關(guān)位置關(guān)系,正確運(yùn)用共線向量和平面向量的基本定理,計(jì)算向量的模、兩點(diǎn)的距離等。由于向量是一新的工具,它往往會與三角函數(shù)、數(shù)列、不等式、解幾等結(jié)合起來進(jìn)行綜合考查,是知識的交匯點(diǎn)。

(1)向量的加法與減法是互逆運(yùn)算;

(2)相等向量與平行向量有區(qū)別,向量平行是向量相等的必要條件;

(3)向量平行與直線平行有區(qū)別,直線平行不包括共線(即重合),而向量平行則包括共線(重合)的情況;

(4)向量的坐標(biāo)與表示該向量的有向線條的始點(diǎn)、終點(diǎn)的具體位置無關(guān),只與其相對位置有關(guān)系;

試題詳情

題型1:平面向量的概念

例1.(1)給出下列命題:

①若||=||,則=

②若A,BC,D是不共線的四點(diǎn),則是四邊形ABCD為平行四邊形的充要條件;

③若==,則=

=的充要條件是||=||且//;

⑤ 若////,則//

其中正確的序號是      。

(2)設(shè)為單位向量,(1)若為平面內(nèi)的某個(gè)向量,則=|;(2)若與a0平行,則=|;(3)若平行且||=1,則=。上述命題中,假命題個(gè)數(shù)是(   )

A.0               B.1               C.2               D.3

解析:(1)①不正確.兩個(gè)向量的長度相等,但它們的方向不一定相同;

②正確;∵ ,∴ ,

AB,CD是不共線的四點(diǎn),∴ 四邊形 ABCD為平行四邊形;反之,若四邊形ABCD為平行四邊形,則,

因此,

③正確;∵ =,∴ ,的長度相等且方向相同;

,∴ 的長度相等且方向相同,

的長度相等且方向相同,故

   ④不正確;當(dāng)//且方向相反時(shí),即使||=||,也不能得到=,故||=||且//不是=的充要條件,而是必要不充分條件;

   ⑤不正確;考慮=這種特殊情況;

   綜上所述,正確命題的序號是②③。

點(diǎn)評:本例主要復(fù)習(xí)向量的基本概念。向量的基本概念較多,因而容易遺忘。為此,復(fù)習(xí)時(shí)一方面要構(gòu)建良好的知識結(jié)構(gòu),另一方面要善于與物理中、生活中的模型進(jìn)行類比和聯(lián)想。

(2)向量是既有大小又有方向的量,與||模相同,但方向不一定相同,故(1)是假命題;若平行,則方向有兩種情況:一是同向二是反向,反向時(shí)=-||,故(2)、(3)也是假命題。綜上所述,答案選D。

點(diǎn)評:向量的概念較多,且容易混淆,故在學(xué)習(xí)中要分清,理解各概念的實(shí)質(zhì),注意區(qū)分共線向量、平行向量、同向向量等概念。

題型2:平面向量的運(yùn)算法則

例2.(1)如圖所示,已知正六邊形ABCDEFO是它的中心,若==,試用將向量,, 表示出來。

(2)(06上海理,13)如圖,在平行四邊形ABCD中,下列結(jié)論中錯(cuò)誤的是(    )

A.  B.+  C.  D.+

(3)(06廣東,4)如圖1所示,D是△ABC的邊AB上的中點(diǎn),則向量(   )

A.      B.

C.       D.

(1)解析:根據(jù)向量加法的平行四邊形法則和減法的三角形法則,用向量來表示其他向量,只要考慮它們是哪些平行四邊形或三角形的邊即可。

因?yàn)榱呅?i>ABCDEF是正六邊形,所以它的中心O及頂點(diǎn)A,BC四點(diǎn)構(gòu)成平行四邊形ABCO,

所以=+,= =+,

由于AB,OF四點(diǎn)也構(gòu)成平行四邊形ABOF,所以=+=+=++=2+

同樣在平行四邊形 BCDO中,+(+)=+2。

點(diǎn)評:其實(shí)在以AB,CD,EFO七點(diǎn)中,任兩點(diǎn)為起點(diǎn)和終點(diǎn),均可用 ,表示,且可用規(guī)定其中任兩個(gè)向量為,,另外任取兩點(diǎn)為起點(diǎn)和終點(diǎn),也可用表示。

(2)C.

(3),故選A。

例3.設(shè)AB、CD、O是平面上的任意五點(diǎn),試化簡:

,②,③。

解析:①原式=

②原式= ;

③原式=

例4.設(shè)為未知向量,為已知向量,解方程2-(5+3-4)+ -3=0

解析:原方程可化為:(2 - 3) + (-5+) + (4-3) = 0,

=+ 。

點(diǎn)評:平面向量的數(shù)乘運(yùn)算類似于代數(shù)中實(shí)數(shù)與未知數(shù)的運(yùn)算法則,求解時(shí)兼顧到向量的性質(zhì)。

題型3:平面向量的坐標(biāo)及運(yùn)算

例5.已知中,A(2,-1),B(3,2),C(-3,1),BC邊上的高為AD,求。

解析:設(shè)D(x,y),則

所以。

例6.已知點(diǎn),試用向量方法求直線(為坐標(biāo)原點(diǎn))交點(diǎn)的坐標(biāo)。

解析:設(shè),則

因?yàn)?sub>的交點(diǎn),所以在直線上,也在直線上。

即得,由點(diǎn)得,。

得方程組,解之得

故直線的交點(diǎn)的坐標(biāo)為。

題型4:平面向量的性質(zhì)

例7.平面內(nèi)給定三個(gè)向量,回答下列問題:

(1)求滿足的實(shí)數(shù)m,n;

(2)若,求實(shí)數(shù)k;

(3)若滿足,且,求

解析:(1)由題意得,所以,得

(2),

(3)

由題意得,得

例8.已知

(1)求;

(2)當(dāng)為何實(shí)數(shù)時(shí),平行, 平行時(shí)它們是同向還是反向?

解析:(1)因?yàn)?sub>

所以

(2),

因?yàn)?sub>平行,所以即得。

此時(shí),則,即此時(shí)向量方向相反。

點(diǎn)評:上面兩個(gè)例子重點(diǎn)解析了平面向量的性質(zhì)在坐標(biāo)運(yùn)算中的體現(xiàn),重點(diǎn)掌握平面向量的共線的判定以及平面向量模的計(jì)算方法。

題型5:共線向量定理及平面向量基本定理

例9.(2002天津文12,理10)平面直角坐標(biāo)系中,O為坐標(biāo)原點(diǎn),已知兩點(diǎn)A(3,1),B(-1,3),若點(diǎn)C滿足,其中α、β∈R,且α+β=1,則點(diǎn)C的軌跡方程為(   )

A.3x+2y-11=0                   B.(x-1)2+(y-2)2=5

C.2xy=0                       D.x+2y-5=0

解法一:設(shè),則

,

于是,先消去,由

再消去,所以選取D。

解法二:由平面向量共線定理,

當(dāng)時(shí),A、B、C共線。

因此,點(diǎn)C的軌跡為直線AB,由兩點(diǎn)式直線方程得即選D。

點(diǎn)評:熟練運(yùn)用向量的加法、減法、實(shí)數(shù)與向量的積的坐標(biāo)運(yùn)算法則進(jìn)行運(yùn)算;兩個(gè)向量平行的坐標(biāo)表示;運(yùn)用向量的坐標(biāo)表示,使向量的運(yùn)算完全代數(shù)化,將數(shù)與形有機(jī)的結(jié)合。

例10.(1)(06福建理,11)已知︱︱=1,︱︱=,=0,點(diǎn)C在∠AOB內(nèi),且∠AOC=30°,設(shè)=m+n(mn∈R),則等于(  )

A.        B.3       C.     D.

(2)(06湖南文,10)如圖:OMAB,點(diǎn)P由射線OM、線段OBAB的延長線圍成的陰影區(qū)域內(nèi)(不含邊界).且,則實(shí)數(shù)對(x,y)可以是(  )

A.   B.

C.      D.

解析:(1)B;(2)C。

題型6:平面向量綜合問題

例11.已知向量的對應(yīng)關(guān)系用表示。

(1)證明:對于任意向量及常數(shù)m,n恒有成立;

(2)設(shè),求向量的坐標(biāo);

(3)求使,(p,q為常數(shù))的向量的坐標(biāo)

解析:(1)設(shè),則

,

(2)由已知得=(1,1),=(0,-1)

(3)設(shè)=(x,y),則,

∴y=p,x=2p-q,即=(2P-q,p)。

例12.求證:起點(diǎn)相同的三個(gè)非零向量,3-2的終點(diǎn)在同一條直線上。

證明:設(shè)起點(diǎn)為O,=,=3-2

=2(),=,

共線且有公共點(diǎn)A,因此,AB,C三點(diǎn)共線,

即向量,3-2的終點(diǎn)在同一直線上.

點(diǎn)評:(1)利用向量平行證明三點(diǎn)共線,需分兩步完成:① 證明向量平行;② 說明兩個(gè)向量有公共點(diǎn);

⑵用向量平行證明兩線段平行也需分兩步完成:①證明向量平行;②說明兩向量無公共點(diǎn)。

試題詳情


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