What would you say to show agreement?

That's right.

Absolutely!

Exactly!

I agree.

I agree with you.

I think you are right.

Yes, I think so too.

I see what you mean.

That is a good point.

That's exactly how I fell.

That is what I think too.

I agree with you 100%.

I couldn't agree more.

(=I agree 100%.)

You could say that again!

(used when emphasizing)