请问针对I will be back (in a moment).句子中括号部分如何提问,用When,How long还是How soon?

问题描述:

请问针对I will be back (in a moment).句子中括号部分如何提问,用When,How long还是How soon?

How soon

用How soon

答案是How soon 多久以后,表将来.
(而when是用于对时间点的提问,how long 是用于对一段时间的提问)

When will you be back?