forget（slip one's mind/memory)

形容“完全不记得，忘得一干二净”

I completely forgot.

我忘得一干二净

It completely slipped my mind.

我忘得一干二净

It completely slipped my memory.

我忘得一干二净

absent-minded

指非常健忘

I am absent-minded these days.

我最近很健忘

amnesia

健忘症、失忆症

I have amnesia.

我得了失忆症

mix up/ confuse

两者是同义词，表混淆的意思

You've got me mixed up with Steve.

你把我和Steve搞混了。

I think you're mixing me up with Sam.

我想你是把我和Sam弄混了。