You have to wear special clothing, a helmet and a life jacket ____ your raft gets turned upside down or sinks.
Go on _______ the other exercise after you have finished this one.
There was a terrible noise ______ the sudden burst of light.
If it is fine tomorrow, we ______ a football match.
When he was at school, he ______ early and take a walk before breakfast.
In the past 30 years China ______ great advances in the socialist revolution and socialist construction.