let in on

US /let ɪn ɑːn/
UK /let ɪn ɑːn/
"let in on" picture
1.

알려주다, 끼워주다

to allow someone to share a secret or to know something that is not known by many people

:
They finally let me in on their plans for the surprise party.
그들은 마침내 나를 깜짝 파티 계획에 끼워주었다.
She refused to let him in on the secret.
그녀는 그에게 비밀을 알려주기를 거부했다.