21．This is the first time we ________a film in the cinema together as a family.
A．see B．had seen C．saw D．have seen
22．Ladies and gentlemen, please fasten your seat belts. The plane .
A．takes off B．is taking off C．has taken off D．took off
23．The joy of life is a deep spring. Only when digging deep ______ clear and sweet water.
A．you can draw B．did you draw C．can you draw D．you draw
