他们俩彼此不认识用英语怎么说

这句话用英语表达为 "They don't know each other."

其中, "they" 是指两个人, "don't" 是 do not 的缩写, 表示否定, "know" 是动词，表示认识， "each other" 是代词短语，表示彼此

英文例句：

They don't know each other, so they were introduced by a mutual friend.
The two strangers on the train didn't know each other, but they struck up a conversation.
They hadn't met before, so they didn't know each other.

中文翻译：

他们彼此不认识，所以是由一位共同的朋友介绍认识的。
火车上的陌生人彼此不认识，但他们开始了一场对话。
他们之前没有见过面，所以彼此不认识。