Knit (one's) brow(s) American British verb phrase
To draw one's brow together for being worry or thinking carefully
If any disputes arise in the meeting, John will find a ventilating space, knit his brow for a while, and then come back to continue.
When Jane's parents asked him about the exam, he shook his head, knitted his brows, and went straight to his room.
My mom keeps knitting her brows when witnessing the toddle of the grandchild.
The verb "knit" should be conjugated according to its tense.
A humorous way of saying that what one has said is just what they acknowledge and may not be entirely accurate
Mike: Have you returned from your vacation on the beach? Your skin seems to get tanned.
Jenny: My skin is always dark. That's my story and I'm sticking to it!