This morning traffic was ____ by an accident outside the town hall.

Don’t be joking. It’s time to ______ your business.

People are _________the use of alternative energy sources. Because the fossil fuels _________will be used sooner or later.

Practising Chinese kungfu (功夫)can not only ____ one’s strength, but also develop one’s character.

It is sometimes difficult for a newly established corporation to ______ the changing demands of the market.