spring on

US /sprɪŋ ɑːn/
UK /sprɪŋ ɑːn/
"spring on" picture
1.

突然提出, 突然告知

to suddenly present something to someone, especially in a surprising or unexpected way

:
Don't spring that question on me now; I need time to think.
别现在突然把这个问题抛给我;我需要时间思考。
They decided to spring the news on him at the party.
他们决定在派对上突然告诉他这个消息。