20.There used__________a post office at the corner of the street.
This vase wasn't________properly before it was put away.
________the farmers were pleased the good harvest of this year.
My father made me a promise________I got a good mark he would buy me a present.
Instead of________, Hawing went on with his research, got his PhD and married the girl.
The girl ________to be a good dancer if she is well trained in an art school.