Occasions are quite rare ________ I have time to spend a day with my kids.

Could you tell me something about the virus, Dr. Smith — Sure. It _____ via the bloodstream and causes ill health in a variety of organs.

Excuse me, could you please tell me if the sports meeting ______ on time — It’s hard to say. It depends on the weather. If it ______ tomorrow, we’ll have to put it off.

What a big difference Tu Youyou has made to modern medicine in the world！She says she will________ her study.

A new library is being built ______ there was a playground.