Cars play an important role in modern life, but they_______also cause many problems like air pollution．

Jane requested that Mr. Smith _________ her another chance.

I insisted _____ to see a doctor, but he insisted nothing ____ wrong with him.

Bob insisted that he ________ nothing wrong and _______ from work.

“Mike is often absent from class.” “Tell him he _____ answer for it if he goes on behaving like that.”