唯一有一個困難就是要如何猜測其他人當時的情緒。

唯一有一個困難就是要如何猜測其他人當時的情緒。

結果 (英文) 1:

The only difficulty is how to guess the emotions of other people at the time.

結果 (英文) 2:

The only difficulty is how to guess other people's emotions at the time.

結果 (英文) 3:

The only difficulty is how to guess how other people were feeling at the time.