Thanks JoeF for all the clarification. However, I am still not clear about the 'temporary' part. You tried to give an explanation that event ( reason for travel abroad) needs to have a 'termination date'. But that is easy to define. For example,
1. If you are an emplyee of a US firm, you can show the project deadline or contract.
2. If you or a student, you can show graduation date.
3. If you are visiting to take care of elderly parents then you can show the treatment records.
According to you, a 5 years of study is still temporary because it has an ending date.
In life there is no such event that does not end and in life there is nothing such as 'Permanent'. (We are all temporary residents of this earth.)
What the officer looks for is 'intent' and as long as one can show a strong reason to come back to America then the officer can not deny. For example, what happens to someone's wife who went abroad to take care of elderly parents and stayed there for two years while the husband visited wife abroad on a regular basis? Is officer going to deny wife when she comes back? And if she used ReEntry Permit and stays like that for 2 more years, is that a ground for denial?