In the experiment we kept a watchful eye （ ） the developments and recorded every detail.

Many people prefer the bowls made of steel to the______ made of plastic.

The local government is trying all out to find out who is （ ） the forest fire.

It is important that the boy （ ） an adult to take care of him.

Many students thought about the third question for quite a while and had great difficulty answering it. Obviously， it was _____ all.

He （ ） me to give up the holidays in Spain next month.

（ ） some mammals came to live in the sea is now known.

Do you mean this is the_____decision you have made after thinking for hours?

What （ ） would happen if he told mom and dad what we had done?

Such a skilled tennis player knows how to take_____of his opponent’s (对手) chief weakness.

I left for the office earlier than usual this morning （ ） traffic jam.

I have seldom seen my father _____ pleased with my progress as he is now.