___you go across the road,you must be careful

___you go across the road,you must be careful
a.since b.after c.when d.before
They won't be back home until the work___
a.was done b.will be done c.is done d.had been done
Olive was so busy___a novel that he ___to have dinner
a.reading,forgets b.to read,forgets
c.to read,forget d.reading,forgot
They set out__for the___boy
a.searching ,losing b.searching,lost
c.to search,lost d.to search,missed
She ___the book and wanted to find the answer.
a.looked through b.looked over c.looked at
Please___before you decide___to do it.
a.think it about,what b.think it over,how
c.think it about,how d.think it of,what

c/c/d/c/a/b
第一题：
_When_you go across the road,you must be careful
a.since b.after c.when d.before
选 C ,When.
A since 是“自从...后”的意思,以since开头的状语从句后面的主句一般都是现在完成时.如：Since the war,I have been there many times.(自那次战争以来,我曾去该地多次.)
B.after,是“在...之后”的意思,如选择B,则字面意思为“当你过马路后,一定要小心.”明显不符合常理.
C.when,是“当...时候”的意思,如：When I came home my wife was cooking dinner.（我回家时,妻子在做晚饭.）
D.before,是“当...之前”的意思,如选择D,则字面意思为“当你过马路之前,一定要小心.”也不符合常理.
第二题：
选择c.
They won't be back home until the work___
a.was done b.will be done c.is done d.had been done
这道题是考察学生是否掌握“主将从现”的典型题目.如掌握了这道题,以后类似的题目绝对不会再错.
所谓“主将从现”是指主句是将来时,从句一定是现在时.
这道题的主句是“They won't be back home”,从句就应当是“until the work is done”——现在时态.
a.was done 是过去时态；
b.will be done 是将来时代；
d.had been done 是过去完成时态；
所以a,b,d,都不正确.
第三题
选择d.
Olive was so busy_reading_a novel that he _forgot_to have dinner.
a.reading,forgets b.to read,forgets
c.to read,forget d.reading,forgot
这道题主要考察两个点：
1.busy doing 和 busy to do 的区别；
2.so...that...用法；
首先解释“busy doing”和“busy to do”的区别：
busy doing 是指正在忙于做某事,如 He is busy answering letters.
(他正忙于回信.)
busy to do 是指将要忙于做某事,如 He is busy to pack up for his working post.(他正忙着准备行装去新的工作岗位.)
所以此句应是 Olive正在忙于读小说,而不是她准备忙着去读小说,所以应是“Olive was so busy_reading_a novel”.
其次是so...that 太...以致...的意思,其前后时态要一致,
此句前面的时态就是过去时,所以后面还用过去时态,forgot.
第四题
选择C.
They set out_to search_for the_lost_boy.
a.searching ,losing b.searching,lost
c.to search,lost d.to search,missed
set out to do 动词不定式,固定搭配,请记住.
losing作为形容词表示失败的意思,而missed 作为形容词表示错过的意思.只有lost作为形容词表示“丢失”的意思.
第五题
选择a.
She _looked through_the book and wanted to find the answer.
a.looked through b.looked over c.looked at
look through是“审核,浏览,温习,彻底审查”的意思；
looked over 是“察看,检查,原谅,调查”的意思；
look at 是“看,着眼于”的意思；
所以选择a,译为她把书翻遍了来寻找答案.
第六题
Please_think it over_before you decide_how_to do it.
a.think it about,what b.think it over,how
c.think it about,how d.think it of,what
think over 意思是“仔细考虑,重新考虑”,固定搭配,请牢记.
think it about 完全错误,没有这种用法,应是think about it.
think it of 完全错误,也没有这种用法,应是think of it.
what to do it 完全错误,绝对有这种用法,只有 what to do 或 to do it.
回答完毕.:)