slowly的比较级为more slowly；高水平为most slowly。一般两个音节以下的词，比较级和高水平都加er、est，但由形容词加ly的，一般有more和most。slowly是副词，其意思是慢速地、缓慢地、迟缓地，例如to move slowly慢慢移动、slowly but surely缓慢但扎实地。

例句：1、The car slowly climbed the hill.

汽车缓慢地爬上了山坡。

2、He found that life moved slowly in the countryside.

他发现乡村的生活节奏慢。

3、The stream meanders slowly down to the sea.

这条小河弯弯曲曲缓慢地流向大海。

4、He shook his head slowly from side to side.

他慢慢地摇了摇头。

5、My mother's hospital expenses were slowly draining my income.

我母亲的住院开销把我的收入渐渐耗光了。