1.agree with

①表示同意某人或某人的意见、想法、分析、解释等 (即持同一观点)

I don’t agree with you.

我不同意你的意见。

They agreed with this idea.

他们同意这个想法。

I agree with what you say.

我同意你说的。

②表示“ (食物、天气、工作等)对…适宜”

The weather doesnot agree with me.

这种天气对我不适宜。

Hard work does notagree with him.

艰苦的工作对他不适宜。

③表示“与…一致”

A verb must agree with its subjectin person and number.

动词必须和它的主语在人称和数方面保持一致。

What he does does not agree with what he says.

他言行不一致。

2. agree to

①主要用来表示一方提出一项建议、安排、计划等，另一方同意协作

We agreed to their arrangement.

我们同意了他们的安排。

She agreed to marriage.

她同意结婚。

有时 agree to 也可用来表示“答应”一件自己不愿做的事

I was forced to agree to it, but at heart I didn’t quite agreewith it.

我被迫答应，但内心并不完全同意。

②后接 suggestion, plan, proposal 等名词时，与 accept 同义：

Do you think he will agree to (=accept) my suggestion?

你认为他会同意 (接受)我的建议吗?

③其后既可接动词原形 (此时to是不定式符号)，也可接动名词 (一般有逻辑主语，此时 to是介词)

He agreed to go with us.

他同意同我们去。

I never agreed to Mary marrying him.

我从来没同意玛丽嫁给他。

3. agree on [upon]

①主要指双方通过协商而取得一致意见或达成协议

We agreed on the price.

我们就价格达成了一致意见。

Both sides agreedon these terms.

双方都同意这些条件。

②后接动名词 (=agree to do sth)

He agreed on lending (=to lend) us some money.

他同意借给我们一些钱。

Mary agreed oncoming [to come] on Monday.

玛丽同意星期一来。

4. 两点用法说明

(1) 后接表示人的名词或代词时，一般只用 agree with。

(2) agree 不能接不定式的复合结构，所以汉语的“同意某人做某事”，不能直译为 agree sb to do sth, 而应根据情况改用其它结构：

他们同意我去。

正：They agreed to let me go.

正：They agreed to my going.

误：They agreed me to go.