Somehow I got out of my depth in the pool.

不知什么原因我在池子里没了顶。

《柯林斯英汉双解大词典》

I'm out of my depth when it comes nuclear physics.

我对原子物理学一窍不通。

youdao

I'm afraid organizing a conference might be out of my depth.

组织一次会议恐怕非我力所能及。

youdao

"I loved doing the play and I did feel slightly out of my depth, " Smith told the BBC after collecting her award.

BBC: Sheridan Smith and Rupert Everett shine at theatre awards

Here the careful reader will note I'm wildly out of my depth.

WSJ: 2013 Mercedes-Benz GL350 BlueTec Review: A Quiet-Tuned Land Megayacht | Rumble Seat by Dan Neil

I'm out of my depth.

BBC: Transcript: Cocaine: Alex James in Colombia