since+瞬间性动词的疑问It is two years since you come to see me.It is two years since you come here.since后面+的都是瞬间性动词,但第一句表示的是否定,两年没看了,第二句表示的是肯定来了两年了.请问这个since+瞬间性动词表肯定还是否定有没有什么规律判断?把 come 改成came。

since+瞬间性动词的疑问
It is two years since you come to see me.
It is two years since you come here.
since后面+的都是瞬间性动词,但第一句表示的是否定,两年没看了,第二句表示的是肯定来了两年了.
请问这个since+瞬间性动词表肯定还是否定有没有什么规律判断?
把 come 改成came。