I wouldn't be dropping in to see anyone on my way through.

A lot of her friends dropped by to see it.

Tomorrow morning, I'll be back and drop in to see you.

"I just dropped in to see how you were getting along."

As a matter of fact I just dropped in to see if we couldn't get together.

"I understand that you called this morning, and have been dropping in to see me since then."

Matter of fact, that was what I dropped in to see you about.

Just thought I'd drop by to see my old buddy.

I dropped by to see him yesterday, talked over old times.

Saw his wife last Friday, when she dropped in to see him at work.