Wrestling with expressing myself

While I am able to appreciate the different grammatical structures in different languages, I feel stumped that I have not been able to express certain sentences that I feel to be very basic. I have no problems expressing these sentences in Chinese.

1. These two sentences sound natural to me: How was work today? How was school today?
But these two do not: How was your studying (not necessarily school, possibly self-study session) today? How was your traveling today?
In Chinese, this is what I would ask: ? (you) ?? (today) ?? (study) ??? (how)? ? (you) ?? (today) ?? ??? (how)?

2. What question should I ask to get the following answer?
A: Barack Obama is the 44th president of the United States.
Is the following a sufficiently well expressed question?
Q: Which (numbered) president of the United States is Barack Obama?
In Chinese, this is what I would ask: ??? (Obama) ? (is) ?? (America) ? (of) ??? (number what) ?? (president)?

Any thoughts from the community?