Why do you think that?
I'm quite certain that...
I'm personally of the mind that...
Positively, because...
There's a lot in what you're saying. However...
My personal view is that...
Are you certain about that?
That's very true, because...
In a way you're right, but I think it all depends on...
I see what you're getting at, but...
As I see it...
I see what you mean, but on the other hand...
You're absolutely right. For example, when...
Do you really think so?
Right, especially if...
If you ask me...
What makes you say that?
It seems to me that...
I'm positive (that)....
In my view...
I'm not sure I totally agree, because...
