The professor returned just as she had taken a bite of sandwich.

The professor returned to give his reasons some minutes later.

The professor has returned to Nigeria after completing his appointment.

The professor hadn't returned from St. Peter, if that was where he had gone.

The professor returned just in time to see the sergeant spit on him.

"I have used it," returned the professor, with a smile.

But the professor, halfway through his steak, returned to the topic.

I'm sure the professor will return as soon as he is able to.

The professor returned his attention to the three of them.

The little professor returned to his station wagon and drove off.