We just have to do some serious thinking, that's all.

Have something to eat while we do some serious thinking.

She didn't hurry, using the time to do some serious thinking.

I'm just going out to do a little serious thinking.

He had his dinner sent up, and arranged himself to do some serious thinking.

"Throughout history, only a small number of people have done the serious thinking for everybody."

I sat down in a chair to do some very serious thinking.

"That and the threat of a criminal action might make a man do some serious thinking."

Open Mind is supposed to clear your head for serious thinking.

Another does her most serious thinking while in the shower.