. In our class, when the bell rang and the teacher closed his book, it was a ______for everyone to stand up.

In order to attract more customers, many supermarkets usually sell their goods at a good________ at weekends. 

A _____ carries all kinds of things , but no passengers.

It is believed that health problems are closely connected with bad eating habits and a _______ of exercise.

 ---- When shall we start? ---- You are to gather at the _______ at 8:00 tomorrow morning.