分不清

can't tell apart

→ 分
phrase Rare #26,538
can't tell apart Used when you cannot distinguish between things or identify which is which.
CH: 我分不清这两个名字。
EN: I can't tell these two names apart.

分不清哪个才是我

I can't tell which one is really me.

— Hi, Mom (2021)

我分不清

I can't tell them apart.

— 完美陌生人 (2016)

分不清哪是雨水哪是泪水

I can't tell which is rain and which is tears.

— Hi, Mom (2021)

我分不清。

I can't tell the difference.