Question

i agree with you 为什么要加with?

Answer 1

因为这里是不及物动词,agree一般与with连用，agree with sb.，表示同意某人的观点
agree vt. ＆ vi. 基本用法如下

1)单独使用，表示同意、答应等。如：

①I asked him to help me and he agreed.

我请求他帮忙，他答应了。

②After a short time, the program was agreed.

过了一会儿，这项计划大家都同意了。

2)跟介词with连用. 表示"同意；赞成"；"与……一致；(气候，食物)适合"。

例如：①I quite agree with what you said.

我很同意你说的话。

②I don"t quite agree with their methods(opinions, ideas).

我不太赞成他们的办法(意见，想法)。

③The verb must agree with the subject in person and number.

动词在人称和数上应与主语一致。

④The enemy generals could not agree with one another; they quarrelled the whole night. 敌军将领意见不一致，争吵了一整夜。

Answer 2

不省， 应该说： I agree with （what )you said ①I think the coolest thing is sunglasses. 对 1. with不要去掉。应该是：I agree with