1.He hurried back only___his old friend wainting for him in his room.
A. found B.to find C.having found D.finding
为什么选B?
2.The key ___the disagreement was to meet all the people's demands.
A.to solving B.to solve C.solving D.solved
为什么选A?
3. The bank is reported in the newspaper___in broad daylight yesterday.
A.being robbed B.having been robbed C.to have been robbed D.to be robbed
为什么选C？

1.only to 固定搭配。意思是，不料竟会。。。

2. key 作为“关键”讲时，“×××的关键”用key to sth。这里的to应该是介词，后面接名词，所以才用to solving.

3。be reported to do 据说，据传，据报道。固定用法。同样用法还有be said to do. 这样就淘汰了a,b 题目讲的是已经发生的事情，为了强调“已经”的时间，就要用完成时态的被动。