The lady in red ___ be over fifty! She looks so young.A. must B. can C. can’t
Some researchers believed that there is no doubta cure for AIDS will be found.
You’d better _____ some money for special use.
Many studentspreparing for the midterm examination.
________ from space, the earth , with water_______ seventy percent of the surface , looks like a blue ball.
— What made her so sad? — _____ she failed in the examination.