Still I have a question and need more of your help.^^

I still don't understand how the present perfect tense can be used in a context which refer to the future behavior. (Simple present tense can refer to the future, I know but the present perfect tense also can refer to the fututure?)


First of all, there is no future tense, but merely means of expressing future time.
1- Shall/will + inf
2- Be going to+inf
3-Progressive aspect, present
4-Simple aspect. present
5-Shall/will + progressive
6-Be+about to +inf
7-Be to+inf

The present perfect tense is never used to refer to the future time


Larry will call Sue after he has spoken to his mom.[/quote]

In this sentense, the present perfect does not refer to the future but to the past. Notice this structure:
After speaking to his mother, Larry will call Sue.
Regards