1. 根据语境从方框中选择恰当的单词填空，有的需要变换形式

rubbish, pollution, service, quiet

1. （1） We should plant more trees to make less air
3. （2） Some students are collectingover there.
5. （3） The park is muchin the morning than in the evening.
7. （4） Everyone is happy with this hotel because it offers good