1. Imagine you have a new pen pal from America. Then ask about 4 questions of him.
2. Pretend you have a new pen pal from America. Then ask about 4 questions of him.
3. Suppose you have a new pen pal from America. Then ask about 4 questions of him.
4. Think you have a new pen pal from America. Then ask about 4 questions of him.
(Are all the expressions grammatiacl? Do we have to use 'had' instead of 'have'?)
2 answers
grammatical? (mistake).....
All are fine except #4. The verb 'think' doesn't work well in this context.
Also, I'd delete 'about' in your sentences. It's not incorrect. It just reads awkwardly.
Also, I'd delete 'about' in your sentences. It's not incorrect. It just reads awkwardly.