Space vehicles were launched into outer space_____search of another living planet.

We mention the importance of giving up smoking once and again, but hardly ______ it.

（ ） we have all the materials ready, we should begin the new task at once.

Her （ ） to the job left her with very little free time．

All the passengers （ ） in the accident were sent to the nearby hospital in no time.

It is （ ） impossible to work with this noise around.

（ ） when she started complaining.

—Shall we invite Tim? —No, it’s too late to invite any more people. _____, he hates parties, you know.

Before using your new pressure cooker, read the following （ ） carefully.

Scientists say it may be five or six years （ ） this medicine is tested on human beings.

Fresh air, enough exercise and nutritious food （ ） to good health.

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