我不知道你为什么不回复我邮件?
I don't know why you did't reply to my email?
I sent email to you,but why did't you write back?
I sent email to you, I don't know why you did't
give your reply to me?
"wonder" 是想知道,正在想的意思,
我想知道你为什么不回复我邮件
我在想你为什么不回复我邮件
I wonder why you didn't reply to my email?