be careful后面如果要加名词，要加介词about，或者加介词of。

be careful about意思是小心，是固定搭配。

例句：

I think you should be careful about talking of the rebels as heroes.

我觉得你说话应该小心，不能把反叛分子当英雄。

扩展资料

It is important, I think, for everyone to be careful about claiming victory.

我想，每个人宣布胜利时都应该慎重。

He really must be careful about thinking aloud. Who knew what he might say?

他的确该注意自己说话不经思索的问题。谁知道他会说些什么？

Be extra careful about personal hygiene.

要非常注意个人卫生。

People should be careful about their possessions and not leave them lying around.

人们应该小心自己的财物，不要随便乱放。

You'll have to be more careful about what you say; you really caught him on the rawwhen you mentioned his first wife.

你以后说话必须注意点，你提到他第一个妻子，这确实触到了他的痛处。