问题描述：
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More trees ______ on the hill .
A,must be planted B,be planted C,can plant D,should plant
We _______ shanghai for two days
A,have been away B,have be away from C,have been away from D,had been away from
what time do you ______ nanning
A,reach to B,get C,arrive D,reach
More trees ______ on the hill .
A,must be planted B,be planted C,can plant D,should plant
We _______ shanghai for two days
A,have been away B,have be away from C,have been away from D,had been away from
what time do you ______ nanning
A,reach to B,get C,arrive D,reach
问题解答：
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