1.Only when the war was over ________to his hometown.
A.did the young soldier return
B.the young soldier returned
C.returned the young soldier
D.the young soldier did return

2.In order to improve English,_________
A.Jenny's father bought her a lot of tapes
B.Jenny bought a lot of tapes for herself
C.a lot of tapes were bought by Jenny
D.a lot of tapes were bought by Jenny's father

3._______no possibility _______Bob can win the first prize in the match.
A.There,that
B.It,that
C.There,whether
D.It,whether

4.Mr.Reed made up his mind to devote all he had to _______some schools for poor children.
A.set up
B.setting up
C.have set up
D.having set up

1.A (理由与楼上相同)
"only修饰句子的状语（从句）位于句首时，句子（主句）要用 部分倒装。部分倒装是指将谓语的一部分如助动词或情态倒装至主语之前。如果句子的谓语没有助动词或情态动词，则需添加助动词do, does或did，并将其置于主语之前"。

2\B
因为提高英语 是Jenny自己的目的，所以发出动作者为Jenny.
如果不能理解，可以尝试调换下语序：Jenny bought a lot of tapes for herself in order　to improve (her) English.
又比如：:<1>In order to catch the first bus,she got up very early.<2>She got up very early in order to catch the first bus. 这两句表达是一个意思．
３\A
是一个句型：there is (no) possibility that．．．．
或者there is (no) possibility of．．．．
比如：①There is not a possibility of talking_2nd Moon ．
②There is no possibility of knowing the unknowable nature of God ．
４＼B
这个题比较刁钻
你一定是疑惑为什么答案是B而不是A吧．
其实，是因为这样的：
在这个句子中，并不是考察不定式，而是考察devote to (doing) sth这个固定搭配.比如：
"After he has retired, he will devote himself to gardening."
"退休后,他将要致力于园艺。"