She had a very shrewd idea of certain troubles connected with the younger generation.

He had a shrewd idea as to what demon I was fighting.

"I think she must have a pretty shrewd idea."

Most of the Yankees thought this was a shrewd idea.

Mallon had a pretty shrewd idea of who was involved.

"You've a very shrewd idea of who was in her mind."

"We've not got a definite identification, but we have a fairly shrewd idea."

Alternatively, a fairly shrewd idea can be obtained by simply looking at the back.

He had a shrewd idea of how matters stood with.

"Yes, and I've got a pretty shrewd idea who the guilty party is."