soon 和 at once的区别(急)

问题描述:

soon 和 at once的区别(急)
He gave him the money immediatly .He gave him the money ( )
A.at once B.soon
我觉得应该选A
但理由是什么?
soon 比 at once表示的间隔时间长?
immediately
不好意思 又拼错了
还有我希望有例句

at once 马上,立即,与mmediatly 同义
soon 不久