我真不知道。用英语怎么说 ? 

我真不知道。的英语翻译是:

I really don't known.

句子单词讲解

1. really
单词释义: adv.真,真正;实在,果真;实际上;事实上
应用场景: CET4|TEM4|考 研|CET6
相关短语:
这样太耽误时间了。
It really takes time.
我玩得很开心。
I really enjoyed myself.
真是笑死我了!
You're really killing me!

2. known
单词释义: adj.大家知道的;已知的;知名的;向某人作自我介绍v.知道( know的过去分词 );看到过;听到过;经历过
应用场景: TEM4
相关短语:
我们认识有六年了。
We have known each other for 6 years.