Don't go too far into the sea, children, or the waves will _____ you off your feet.
—If only there were no examinations! —__________ We all need more rest.
—What's the boys' favorite sport? —__________ of boys like playing football.
Every possible means __________ to prevent air pollution, but the sky is still not clear.
We must __________ to the public the simple fact thatdrugs are dangerous.
That was the first time __________ I __________ face to face with the president.