Each member country of WTO must ______ its laws and regulations and compete on the principle of fairness and co-operation.
Do you know the boy _______ under the big tree?
-What do you think of the book? -Oh, excellent. It’s worth ______ a second time.
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.