Suddenly they'll pop into view and make you feel young indeed.

Before his morning meeting with the team, he would pop into the training room.

Sometimes I think of him, he'll just pop into my head at any old moment.

They just popped into my mind and I didn't need to do another thing about them.

It was the first thing to pop into his mind.

I don't know what made it pop into my head.

However, a whole new set of questions popped into mind.

And all at once a thought popped into her head.

He said the idea popped into his head at a committee meeting.

A plan popped into my mind almost without me thinking.