要选the。
23. The number of giant pandas is getting ______ because their living areas are becoming farmlands.
A. less and less B. larger and larger
C. smaller and smaller D. fewer and fewer
[析] 答案为C。句意为\大熊猫的数量越来越少因为他们的生存空间正逐渐变
成农场\。本题中四个选项都是\比较级+ and + 比较级\的结构，表示\越来越…\。主语为number，只能和large或small搭配。而结合句意可判断答案为C。 24. Be careful when you come _______ the street，because the traffic is very busyat the moment.
A. across B. behind C. between D. over
[析] 答案为A。本题考察方位介词的用法。\过马路\一般为表面横穿，因此
要用across。
25. Do you often clean your classroom?
---- Yes, our classroom _____ every day. A. clean B. cleans C. is cleaned D. Cleaned
[析] 答案为C。句中有every day，主语为our classroom，故要用一般现
在时的被动语态。
26. Lucy usually cleans the cage every two days. (对画线部分提问)
_______ Lucy usually clean the cage?
[析] 答案为How often does。对every two days提问要用how often。
27. I didn't understand __________，so I raised my hand to ask.
A. what my teacher says B. what does my teacher say
C. what my teacher said D. what did my teacher say
[析] 答案为C。本题为宾语从句，由于需要用陈述语序可排除B、D;另外，
主句时态为一般过去时，则从句也要用对应的过去时态，故还可排除A。 28.How much ______ the shoes?Five dollars ______ enough. A. is;is B. are;is C. are;are D. is;are
[析] 答案为B。shoes作主语时，谓语动词应用复数形式;five dollars是一
个整体，应按单数对待。
29.〔 误〕We got to the top of the mountain in daybreak.
(√)We got to the top of the mountain at day break.
[析]at用于具体时刻之前，如：sunrise, midday, noon, sunset, midnight,
night。
30.(×)Don't sleep at daytime (√)Don't sleep in daytime.
[析]in 要用于较长的一段时间之内，如：in the morning / afternoon, 或 in
the week / month / year. 或 in spring / supper /autumn / winter等等。
31. (×)He became a writter at his twenties.
(√)He became a writter in his twenties.
[析]这句话应译为：他在20多岁时就成了作家。在某人的一段生活时间段中
要用介词in来表示，而在具体岁数时用at来表示。
32.〔 误〕We went to swim in the river in a very hot day.
(√)We went to swim in the river on a very hot day. [析]具体某一天要用介词on, 又如：on New Years Day
33. (×)I'm looking forward to seeing you on Christmas.
(√)I'm looking forward toseeing you at Christmas.
[析]在节日的当天用on，而全部节日期间用at , Christmas是圣诞节期间，
一般要有两周或更长的时间。
34. [误] I haven't see you during the summer holidays.
[正] I haven't seen you since the beginning of the summer holidays.
[析]during表示在某一段时间之内，所以一般不与完成时搭配，如：I visited
a lot of museums during the holiday. 而for表示一段时间，可以用于完成时，如：I haven't see you for a long time. 而through 用来表示时间时则为\整整，全部的时间\。如：It rained through the night.而since则是表达主句动作的起始时间，一般要与完成时连用。
35. (×)At entering the classroom, I heard the good news.
(√)On entering the classroom, I heard the good news.
[析]On加动名词表示\一……就\。本句的译文应是：我一进入教室就听见这
个好消息了。又如：on hearing… 一听见， on arrival 一到达就……(on表示动作的名词)
36. (×)In the beginning of the book, there are some interesting stories.
(√)At the beginning of the book, there are some interesting stories.
[析]at the begining与at the end都是指某事物的开始与结束部分，均不指时间
范围，而in the beginning 则是指开始一段时间。in the end=at last是指\最终，终于\之意。
37. (×)Till the end of next week. I will have finished this work.
(√) By the end of next week. I will have finished this work. [析] by 引起的时间状语表示了动作的截止点，其意思为\不迟于某一时
刻将工作做完\，所以主句一般是完成时态。当然可以有将来时态，如：Ill be there by five oclock.而till则表达其一动作一直持续到某一时刻，但句中的动词一定要用持续性动词，而瞬间的截止性动词应用其否定句式，如：I won't finish this work till(until) next weekend.
38. (×)He came to London before last weekend.
(√)He had come to London before last weekend.
(√)He came to London two weeks ago.
[析]before 一般要与完成时连用，而ago则与一般过去时连用。
39. (×)I have studied English for three years since I had come here.
(√)I have studied English for three years since I came here.
[析]since用来表达主句动作的开始时间，所以其引出的从句中应为过去时，而
不能用完成时态。
40. (×)I can help you repair this bike. You will get it after two hours.
(√)I can help you repair this bike. You will get it in two hours.
[析]中文经常讲两小时之后来取，两天内会修好，而这个介词在英文中要用in而
不要用after。其原因有二，①after 多用于过去时，如：I arrived in New York. After three days, I found a job in the bank. ② after 加时间是表达一个不确定的时间范围，如：after three days, 即三天之后的哪一天都可以。所以在许诺若干时间内会完成某事时，一定要用介词in。
41.(×)Three days after he died.
(√) After three days he died. (√)Three days later he died.
[析]after 与 later都可以用来表达一段时间之后，但它们所处的位置不同，
after 在时间词前，而later在时间词后。 42.(×)She hid herself after the tree.
(√)She hid herself behind the tree.
[析]after多用来表达某动作之后，所以有的语法书中称它为动态介词，如：
I run after him. After finishing my homework, I went to see a film. 而behind则多用于静态事物之后。
43.(×)There is a beautiful bird on the tree.
(√)There is a beautiful bird in the tree.
tree.
44.(×)Shanghai is on the east of China.
[析]树上长出的果实，树叶要用on, 而其他外来的人、物体均要用in the
(√)Shanghai is in the east of China.
[析]在表达地理位置时有3个介词：in, on, to。in表示在某范围之内; on表
示与某地区接壤;to则表示不相接。如：Japan is to the east of China. 45.(×)I arrived at New York on July 2nd.
(√)I arrived in New York on July 2nd.
[析]at用来表达较小的地方，而in用来表达较大的地方。at常用于at the
school gate, at home, at a bus stop, at the station, at the cinema, at a small