The air is deadly polluted because some factories don't __________ the rules to protect the environment.
Speaking of what sort of smartness is most desirable in human __________,a friend of mine told me a story.
We should __________ primary importance to job training.
The young man rushed out of the room, _______ into his car and started it hurriedly, _______to get home as soon as possible.
Can you imagine the difficulty I had __________ the game?
— I must apologize for ________ ahead of time. — That's all right.