1.He( )to the lab rhan he set out to do the experiment.(答案是D

1.He( )to the lab rhan he set out to do the experiment.(答案是D）
A.has no sooner got B.no sooner got C.will no sooner get D.had no sooner got
2.The ptice( ),but I doubt whether it will remain so.（答案是C）
A.went down B.will go down C.has gone down D.was going down
3.An awful accident ( ),however,occur the other day.(答案是B）
A.does B.did C.has to D.had to
4.--Excuse me,sir.Would you do me a gavor?
--Of course.What is it?
--I ( ) if you could tell me how to fill out this form.(答案是B)
A.had wondered B.was wondering C.would wonder D.did wonder
5.It is said in the book that Thomas Edison(1847-1931) （ ）the world leading inrentor gor sixty years.(答案是D）
A.would be B.has been C.had been D.was

1.He ( ) to the lab than he set out to do the experiment.(答案是D)
A.has no sooner got B.no sooner got C.will no sooner get D.had no sooner got
这句话可译为：他一到实验室就着手做实验.no sooner … than …是个固定搭配,引导时间状语从句,可译为是“一……就……”,这是个时态标志,一看到这个短语就要想到用过去完成时,所谓过去完成时就是过去的过去,从句用过去时,主句用过去完成时；还有hardly … when …“刚（一）……就……”也要用过去完成时.He had hardly arrived when it began to snow.如果把no sooner或hardly提到句首,主句就要倒装.例如题目：No sooner had he got to the lab than he set out to do the experiment.又如：Hardly had he arrived when it began to snow.
2.The price ( ),but I doubt whether it will remain so.(答案是C)
A.went down B.will go down C.has gone down D.was going down
这句话可译为：价格已经下降了,但是我怀疑是否会一直保持这样.but后面的句子是一般现在时,根据句意价格已经下降了,显然B选项是一般将来时不对；如果A选项,是一般过去时（过去是那样,而现在不是那样了）,过去价格下降了,现在价格没有下降,不符合句意；D选项是过去进行时,过去价格正在下降,现在价格没有下降.
3.An awful accident ( ),however,occur the other day.(答案是B)
A.does B.did C.has to D.had to
这句话可译为：然而前几天一场可怕的事故的确发生了.这句话有个时间标志词the other day,汉语意思是“前几天,不久前的一天”,显然要用一般过去时；本来这句话应该是An awful accident occurred the other day.在题目里,do作助动词,表示强调,后面跟动词原形；however是插入语,把它去掉不看整句话就清晰了.
4.--Excuse me,sir.Would you do me a favor?
--Of course.What is it?
--I ( ) if you could tell me how to fill out this form.(答案是B)
A.had wondered B.was wondering C.would wonder D.did wonder
这句话可以为：--先生,打扰一下,你能帮我一个忙吗?--当然可以.什么事?--我刚才在想你能否告诉我怎么填这个表格.先把C选项排除,没有这个用法；A选项是过去完成时,表示过去的过去,而对话里没有提到过去的过去这个时间点；我刚才在想,是过去,用过去时,可以用过去时wondered,也可以用过去进行时,was wondering“刚才正在想”,B选项正确；D选项,do后面跟动词原形,表示强调,而对话里没有要强调的意思.
5.It is said in the book that Thomas Edison (1847-1931) ( ) the world leading inventor for sixty years.(答案是D)
A.would be B.has been C.had been D.was
这句话可译为：书上说托马斯•爱迪生作为世界领先的发明家长达60年.首先排除A选项,过去将来时,将来会成为发明家,这本书成预言书了；排除B选项,现在完成时,刚刚完成这个动作,刚刚还是发明家,我们都知道爱迪生生活的时代早过去了,爱迪生几十年前是发明家,显然是过去；had been和was都是持续性动词,had been有表示过去完成的含义,但是题目这句话的意思只是侧重说明这是过去的一个事实而已,用was.