let in on

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

秘密を教える, 参加させる

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.
彼らはついに私をサプライズパーティーの計画に参加させてくれた。
•
She refused to let him in on the secret.
彼女は彼に秘密を教えることを拒んだ。
:
informdiscloserevealappriseenlighten
:
letlet inlet onlet'slet downlet uplet off