Whoit be that is knocking at the door?——Itbe Father, but I’m not sure.

Is it only when you fail _________ you will be awareof your mistakes

It’s surprising that Mr. Ma’s little daughter _____ speak English so well.

Bing Xin is famous ________children’s works.

They were determined to carry out the plan at first, but then we ________ persuade them to change their minds.