let in on
片語動詞所屬單字let
let in on — 片語動詞
1. To allow someone to know a secret or participate in something.
1.片語動詞
釋義
告知（秘密）；讓...參與
To allow someone to know a secret or participate in something.
例句
They let me in on their plan to surprise her.
Will you let me in on the secret?