Yap.Town

を見分けるのは

to tell … apart is

→ を
phrase Rare #37,207
to tell … apart is The phrase follows the things being distinguished and presents telling them apart as the topic of the sentence.
JA: 双子を見分けるのは難しい。
EN: It’s difficult to tell the twins apart.

君と君の弟を見分けるのは難しい。

It's hard to tell you and your younger brother apart.

彼と彼の兄を見分けるのは簡単だ。

It's easy to tell him and his brother apart.

本物と偽物を見分けるのは困難だ。

It’s difficult to distinguish between the real thing and a fake.

日本人と中国人を見分けるのはいつもやさしいとは限らない。

It isn't always easy to tell Japanese people from Chinese people.