Well, you know what they say. ____________.

I could hardly understand ______ in class, so I raised my hand to ask.

It seems that Mr. Wu is standing there.— It ______ be him because he called me from Canada just now.

You seem to like sweets.—_______. That’s probably why I’m becoming fatter and fatter.

I was about to go to bed _____ one of my old classmates made a call to me.