It was a pity that the great scientist died his research unfinished.

What __heavy rain it was！—Yes, but I love___ air after it rains. It smells so fresh.

We found it difficult _______ there ontime.

I don’t like any humor in serious speech because I can’t think of any _______ where this would be beneficial or useful.

You can’t expect a baby to ________ your existingroutine.