原因 Reason

询问理由 Asking for reason

Why?

Have you got any idea why?

do you know why?

Why do you think?

why did?

What?

What’s the reason?

How did it come about that?

Is that why?

Is that the reason?

提供理由 Giving reasons

The thing is

The reason was that

The basically reason is that

The reason for … was that…

The reason why … is

It’s because …

Well, because..

Well, you see…

If I could explain

And that’s my reason for …

I believe it’s right for the following reasons.

… Has ample justifications for

I think there’s actually a good case for..