The two companies decided to （ ） on a project concerning animal cloning.

He studies so hard to avoid （ ） at the bottom of the class.

Please （ ） the water tap when you have finished your washing．

It’s too late to go out. _____， it’s going to rain.

Mr. Green said his clients _____ our samples by the end of last month.

The little boy saw the plane_____and burst into flames.

A good many proposals were raised by the delegates，（ ） was to be expected.

He studies so hard to avoid （ ） at the bottom of the class.

The defense computers calculate way to （ ） the enemy missiles.

Harmonious marriage, however, does not necessarily （ ） much sharing of interests and responsibilities.

At the 60th anniversary, the guests sitting in the front are those ______ graduates from the university.

He （ ） yesterday morning, and would stay for three days.