They both sat quietly for a moment, thinking back again.

We explained our situation and asked them to think back a ways.

"I was just thinking back on when we were boys."

Think back a year ago to the last time you went.

Even now, thinking back on it, I couldn't tell you which role he played.

Can we even identify all of them later, thinking back?

Whatever she'd been thinking back then, she couldn't understand it now.

Today I like thinking back on that conversation with my father.

He was silent then, thinking back on what had been.

Now I want you to think back for a time before that evening.