✔ 最佳答案
"Very sooner" sounds incorrect, let us see the why.
"sooner" is the comparative of "soon", which is an adverb whereas
"very" is used as another adverb to describe the adverb/ adjective following it, ie "sooner" in the sentence in question, telling the reader how soon something is.
As in your sentence, there is nothing to compare with, no comparative adverb should be used, the basic form "soon" is okay.
So "very sooner" is incorrect, it should be "very soon"
Secondly
"Soon" means "within a short time", used to describe something happen not long after now. Like:
1) We shall SOON be home
2) The train will be there SOON
3) It will SOON be 5 years since we came to live in Cairo
In the above examples, we can see "soon" is used to add more information on the WHOLE action, not the subject only
Like in 2), "soon" tells you that how long the train still needs to get here, that is "soon", within a short time.
Hopefully it can help you a bit