A: Nancy doesn’t look very well. What’s wrong with her? B: She has a terrible headache because she ______ too long. She should stop to have a good rest.

 Please don’t phone him between 1 and 3 p.m. tomorrow. He _________ a lecture then.

 Whatever may happen, go on until you succeed, and you _______ what life is all about.

Having you ever ______ in front of thousands of people at a concert, with everyone _____ while you were singing?

Years ago we didn't know this, but recent science ______ that people who don't sleep well soon get ill.