.[亦作 tell by] 从…可看出；通过…判断出：例句:I could tell by his face that he was angry.我能从他的脸上看出他生气了.2.分清…；区别…,把…与…区分开：例句:to tell the real from the false 区别真伪Can you tell an ox from a cow?你分得出公牛和母牛吗?