Words Learning:
litter n.垃圾
eg: Please clean up the litter.请清理这些垃圾。

loudly adj.大声地
eg: Don't speak so loudly in classroom.不要在教室大声说话!

full adj.慢的
eg: Oh, the glass is full.噢，那个杯子满了。

noise n.噪音
eg: I didn't sleep well because of thenoise.
因为噪音,我睡得不是很好。

keep v.保持
eg: Please keep silent!请保持安静!

quiet adj.安静的
eg: Please be qiuet!请安静!