Question

1. I was poor in the past. 2. I am not so rich in the present/at present. 3. I will be rich in the future. ------------------------------ Are they all grammatical? Can we use both 'in the present' and 'at present'? How about 'at the present'? Which one is commonly used?

Answer 1

1 is grammatical but 2 is supposed to read as "I am not so rich in the present" not "at present" and 3 is fine.
"At the present" wouldn't make much sense (To me)
Hope that helps :^)