1.It was ____the old worker came that we____the experiment

1.It was ____the old worker came that we____the experiment
a.until,didn't begin b.not until,began
c.until,began d.not until,didn't begin
2.Not a single word ____last night
a.he said b.said he c.did he say d.had he said
3.No sooner____to shine____it clouded over again
a.the sun had started,than b.had the sun started,than
c.the sun started,when d.did the sun started,when
4.____are the days when teachers were looked down upon
a.Gone b.Go c.To go d.Going
5.In the open boat ,the four men ,____was a docter,met with a storm at sea.
a.one of which b.one of who c.one of whom d.one of them
6.Nobody has the right to go there to have dinner free,____?
a.hasn't it b.has it c.haven't they d.have they
7.I decided to pay a visit to my former teacher as soon as I____
a.finish what I did b.finished what I did
c.would finish what I was doing d.finished what I was doing
8.Most people usually have less money at the end of the month than____at the begining
a.which is b.which was c.they have d.it is
9.-____in this street?
-I think Mr.Black is the richest man.
a.Whom do you think is the richest man
b.Who do you think is the richest man
c.Do you think who is the richest man
d.Do you think whom is the richest man
说明理由并翻译
理由再具体一些，尤其是6、8题

1.选B,这是固定搭配：it's not until···that···,“直到··才·”
如果选D,则是：直到这个老工人来我们才不开始实验.
B的意思是：直到老工人来我们才开始实验.（两者相比,B更好）
2.选C.当not none等这些含否定意义的词放句首时,句子倒装（即把助动词do does、be动词、情态动词之类的提前到主语前面）,则C的意思是：他昨晚说了不止一个词
3.和第二题一样,句子倒装,选D
4.选D.动词放句首是只有doing和to do形式,to do表目的.D选项的意思是：当老师的那些日子让人看不起,C则是：去当老师的日子让人看不起
5.选D,指人用who 或whom,介词后面用whom
6.选D,主语是人,A B中的it不就是代表不是人嘛.在C,D中选,nobody就是否定,反义疑问句前面否定,后面用肯定
7.选D,前面的decided表示是过去时态,在B D中选,B中的what i did表示我已经做好了,D表示完成我正在做的事,也就是还没完成,完成之后才去看老师
8.选A,这里的which指代Most people usually have money,这样句子更简洁
9.选A,who在think（动词后）用whom.你认为谁是这条街上最富有的人···