Men who spent their lives in space had peculiar ideas as to recreation.

The problem is that you Soviets have a peculiar idea of friends.

His life at home seemed to him to be one long sacrifice to his father's peculiar ideas.

And each person has peculiar ideas about cause and effect in life.

"How did he arrive at such a peculiar idea?"

She has peculiar ideas about things so I can't begin to guess what she's going to do next.

A peculiar idea began to take hold of him.

A peculiar idea occurred to the scholar at that moment, and he smiled.

"Where did you come up with that peculiar idea?"

A peculiar idea to get your head round perhaps but it's all actually pretty straightforward.