Is your brother at home—No. He ________ the library. He hasn’t come back yet.

Though in fact he got，there was no doubt that he had meant to offer help．

Did you do _____ interesting on vacation — Yes, ______ was new for me and we had a great time.

The Greens used to live in London and now they in Beijing.

___ you interrupt now Can’t you see I’m on the phone—Sorry Sir, but it’s urgent.