agree with, agree to,意思是一样的，可是用法不同，他们都是同意某件事或某个人的意见的意思。
1 agree with,的用法是这样的：agree with+doing something或者+somebody
例句：I ageree with going to swim tomorrow.(我同意明天去游泳.)
I agree with you.(我同意你的意见)
2 agree to的用法是这样的：agree to +do something 决不可以agree to somebody.因为agree to 中to后面加动词不定式.指明是动词.
例句:I agree to go to swim tomorrow..(我同意明天去游泳.)
agree to do sth.
表示答应做某事
eg. They agreed to go with us.
决不能说 agree sb. to do sth.
agree on sth.
主语一般是复数形式的名词，表示一致同意。
eg. Both of us agreed on the contact.
要简便点记的话，就记这些：
agree on 双方就某一问题达成一致
agree to + 计划或建议