To protect the environment, the local government has put up a lot of ______ to warn the citizens not to litter the ground.

He once remarked that "All happy families ________ one another, but each unhappy family is unhappy in its own way".

 At the Olympic Games, only the athletes who have reached the agreed standard for their event will be______as competitors.

The teacher asked a very difficult question. It was Ted who finally ____ a good answer.

Caroline __________ staying at home, doing nothing at all. So she has made up her mind to find a job for herself.