请问：翻一个句子

第一个对。应该是一下两种写法。
Why not tell me?
Why don't you tell me?
这两个句子是同义的。第一句是省略说法。

doesn't 用于第三人称单数
得说Why doesn’t she/he/Jim tell me?

第二个

两个都对..
第一句why not do sth...?是固定搭配..多用于口头语...
而第二句是一般写法..多用于书面表达...

第一句对。
why not=why don't you
Why not tell me=Why don't you tell me?
(why doesn't he/she tell me)

第一句对
Why not tell me?=Why don't tell me?

Why not tell me? （第一句对）

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