应该说两个表达都是对的,只是看你怎么用.
反问句时,用“What don't you like?”
从句时,用“..what you don't like..”.
例如：
主语从句 What you don't like is not a secret.
宾语从句 I know what you don't like.
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“你不喜欢什么?”
What do you dislike?