definitely的形容词为definite。definitely作为副词，含义为“肯定”、“当然”、“确切地”、“清楚地”；definite作为definitely的形容词，基本含义为“一定的”、“肯定的”、“明显的”、“有把握”。

definitely作为副词，意为肯定;没问题;当然;确实;确切地;明确地;清楚地。

例句：I definitely remember sending the letter.

我记得这封信肯定发出去了。

Please say definitely whether you will be coming or not.

请说清楚，你来还是不来。

I'm definitely going to get in touch with these people...

我肯定会跟这些人取得联系。

He told them that no venue had yet been definitely decided.

他告诉他们还没有确定下场地。

The whole experience was definitely more positive than negative.

整个经历当然是利多于弊。

Relations between them have definitely cooled.

他们之间的关系已明显地冷下来。

Acting is definitely a young person's profession in many ways.

从许多方面来说，表演无疑是吃青春饭的行当。

definite可作形容词和名词，意为一定的;肯定;确定的;肯定的;不会改变的;清楚的;明显的;有把握；肯定的事(或人)。

例句：Can you give me a definite answer by tomorrow?

你最晚明天能给我一个确定的答复吗？

The look on her face was a definite sign that something was wrong.

一看她的神色就知道出事了。

It's too soon to give a definite answer...

要给出一个明确的答复，现在还为时过早。

We didn't have any definite proof...

我们没有任何确实的证据。

There has already been a definite improvement...

已经有了显著的改进。

If you have any definite news of my husband, please let me know

如果有我丈夫的确切消息，请一定告诉我。