Wrap (one's) head around (something) American phrase informal
The noun "mind" can substitute for the noun "head".
The verb "get" can substitute for the verb "wrap".
If someone "wraps his/her head around something", he/she tries to understand or accepts something that is difficult, strange, or out of ordinary.
She found it hard to wrap her head around complex issues related to astronomy or geology.
I can't wrap my head around this math question.
After her recent breakup, she couldn't wrap her head around true love.
The verb "wrap" should be conjugated according to its tense.
The expression "wrap one’s head around something" seems to have appeared in the 1970s and maybe primarily an American phrase.
If you swallow the bait, you take something that someone offers you, or agree to do something that someone asks you to do without knowing that it is a trick or way of getting something from you.
You can't just do whatever he wants you to do. Don't swallow the bait.