《为什么上线不告诉我 为什么》 英语怎么说

Why don't you tell me when you get online, why?
可再加一句（My heart is broken, 我的心都碎了，哈哈）

Why dodn't you tell me that you are online?
这里要用that才符合句意，that引导的宾语从句，是告诉tell 的内容。不能用when，因为如果用when，意思变成了“当你在线时，为什么不告诉我（其它事情）”

Why don't you tell me when you are on the net?Why?

Why didn't you tell me when you are online?