can you tell Tom (from) his twin brother?I can tell (by) their sm_英语解答

can you tell Tom (from) his twin brother?I can tell (by) their smiles
为什么这两个空要一个填from一个填by呢?

人气：110 ℃　时间：2019-09-20 09:57:36

解答

tell A from B
从B中分辨出A来
tell by…
通过…方式分辨