I can tall you at once.的意思~急~急~急~急~

我能立刻告诉你。

I can't tall you at once
Can you tall me at once?

我能马上告诉你
I can't you at once.
can I tall you at once?

楼主单词打错了吧，应该是tell吧
一楼少了个tell,Ican't tell you at once.

我可以马上告诉你

I can't tell you at once
Can you tell me at once?
另外 问题里的句子应该是 I can tell you at once.