I'm not certain exactly, another voice answered.

As a result, I am not exactly certain what happened.

Sulu shifted uncomfortably, not exactly certain how to proceed.

She wasn't exactly certain what the word 'haunted' meant, but it might be fun to find out.

It is not exactly certain when the practice of presenting the flag came about but is believed to have regularly begun in the early 20th century.

I think they felt not exactly certain of what I might do next.

"Twenty thumpers," he said, though he wasn't exactly certain how much distance that meant.

"I'm not exactly certain, hon. but the first step is to blow our cover."

I'm not exactly certain who it is but there's no possibility of it's being one of the Unseen.

The butler wasn't exactly certain when her ladyship would return.