1、careful是形容词，作定语或表语。

2、carefully是副词，作状语，修饰动词或整个句子。

3、其用法分别如下：

4、 careful

5、[not before noun] ~ (to do sth) | ~ (not to do sth) | ~ (when/what/how, etc.) | ~ (of/about/with sth)

6、小心；注意；谨慎

7、giving attention or thought to what you are doing so that you avoid hurting yourself, damaging sth or doing sth wrong

8、Be careful!

9、He was careful to keep out of sight.

10、他小心翼翼地躲开别人的视线。

11、Be careful not to wake the baby.