It happened gradually; he'd call to talk to the kids, and they'd visit for a few minutes before she handed off the phone.

It tends to happen gradually over a period of time.

This was not, of course, a firm rule: changes in performance style happened gradually.

It happened gradually over a period of months but the transition is at last complete.

That sort of change will happen gradually over time.

This probably goes back to the start of the season, and happened gradually.

As he did so, a picture of what might have happened gradually grew in his mind.

It was happening gradually, but the speed of the process began to increase.

What happens in one place gradually carries over to the whole system.

"These things happen gradually and you get used to it," she said.