So if i wait until i'm a citizen(in next 4 years) then marry her in her home country and file the form , the wait time will be just a year ?(If so,great).I think that way is better ,do you think so ?
That seems about right.
Can i substitute the annual income by a balance in bank ? Or it must be annual income ?
You can use personal assets, though when doing so, you need to have more than the 125% above national poverty. I 'think' its something like 3x the amount, so if the minimum annual income is $18,000, but you want to use assets then you would need to prove that you have $54,000 (I could be wrong on the exact figure, but thats the jist of it).
Can i use somebody's income ( person i know) with their agreement to do that ?
Yes! This is the joint sponsor I mentioned in my previous post to you.
i have to go to college or university so that's probably she can't stay with me in the same place in 5 years ,as i know, if she's not be with me in the same address or place in 5 years after she comes to US,the gov will expel her cos they think our marriage is fake ,is that right ?Maybe she has to be with my parent in CA and i go to some states else to go to university.
Im not sure exactly how this is looked upon by USCIS. So I'll let someone else answer this question.
With my situation,do you know any way else faster to bring her here.I just want to bring her here as soon as possible.
If you want to bring her over, then the quickest way is the option that I have already described to you. If she can qualify for her own visa (ie, work sponsorship, student visa, investment visa etc) then she may be able to get over quicker.