It's a deal.

That's a deal.

You got the deal.

You bet!

That is for sure.

I'd bet on it.

Of course.

That goes without saying.

That's the right thing to do.

I think it's the most sensible thing to do.

It's the wisest thing to do.

Great!

That's great!

Excellent!

Good idea!

Good thinking!

What a good idea!

That's a marvelous idea!

It's a very good idea indeed.

What you say is partly right.

You are partially correct.

I more or less agree with you.

I don't agree.

I disagree.

I am against it.

I am not in favor of it.

I am afraid I can't give my approval.

I wish I could agree with you.

I hate to disagree with you, but...

Objection!

I object!

What a terrible thing to do!

I think that's dreadful.

I don't suppose that's the right thing to do.

I can't buy that.

That's ridiculous.

I refuse to believe that.

Bad idea!

Do you think that's a good idea?

What a terrible idea!

I don't like the idea at all.

Not a good idea.

It's not very nice.

That's not very nice, is it?

Are you kidding?

You must be joking.

You can't be serious.

Nonsense!

Don't be so unreasonable.

Come off it!

Come on!

I really disapprove of this decision.

I am against this decision.

It won't work.

I don't think it'll work.

That's a bit foolish.

That's a bit naughty.

I think you are crazy.

I think you are out of mind.