What is the difference between clothes and clothing?

https://forum.english.best/t/please-answer-my-question-on-english-grammar/46036

1. What is the difference between clothes and clothing?

CHOOSE THE BEST ANSWER: CLOZE TEST
2) The man ___________ the plane talked all the time.
A. who I am sitting next to B. that I was sitting next to him
C. that I was sitting next to D.who I was sitting next him.

3. 1. Everyone was talking but stopped_______ Mr Smith entered the room
      A. at the time
      B. the moment
      C. the time
      D. by the time
4. You mustn’t forget _______ tomorrow morning
   A.turning in your assignment
   B. to turn over your assignment
   C. to turn back your assigment
   D.to turn in your assigment
   
5. You have no idea…then.
   A. what a hard time we had B. we had what a hard time
   C. that we had hard time D. what hard time we had
   
6. Only a …of students attend those classes.
   A. little B. group C. band D.handful
   
7. Find the mistake in the sentence
   I’ve talked to the writer, the works of whom are popular with the youth.
   

The difference between clothes and clothing is outlined here: clothes and clothing 2
As for the rest of the test, what do YOU think the right answers are? =)
By the way, something’s off about sentence #2 - I think it should read “The man ___________ ON the plane talked all the time”

My answer is:
CHOOSE THE BEST ANSWER: CLOZE TEST
2) The man ___________ the plane talked all the time.
A. who I am sitting next to B. that I was sitting next to him
C. that I was sitting next to D. who I was sitting next him.

3. 1. Everyone was talking but stopped_______ Mr Smith entered the room
      A. at the time
      B. the moment
      C. the time
      D. by the time
4. You mustn’t forget _______ tomorrow morning
   A. turning in your assignment
   B. to turn over your assignment
   C. to turn back your assigment
   D. to turn in your assigment
   I already understand why!
   
5. You have no idea…then.
   A. what a hard time we had B. we had what a hard time
   C. that we had hard time D. what hard time we had
   
6. Only a …of students attend those classes.
   A. little B. group C. band D.handful
   
7. Find the mistake in the sentence
   I’ve talked to the writer, the works of whom are popular with the youth.
   -> the work of whom
   

CHOOSE THE BEST ANSWER: CLOZE TEST
2) The man ___________ the plane talked all the time.
A. who I am sitting next to B. that I was sitting next to him
C. that I was sitting next to D. who I was sitting next him.
[color=green]You are incorrect, you are no longer on the plane so present tense would be wrong. C is correct. As Tort pointed out, the preposition ‘on’ is missing from the sentence.

3. 1. Everyone was talking but stopped_______ Mr Smith entered the room
      A. at the time
      B. the moment
      C. the time
      D. by the time
      [color=green]You are correct.
4. You mustn’t forget _______ tomorrow morning
   A. turning in your assignment
   B. to turn over your assignment
   C. to turn back your assigment
   D. to turn in your assigment
   I already understand why!
   [color=green] I’m afraid you don’t understand why, as your choice is incorrect. “To turn in” means ‘to hand in’, so D is correct.
   
5. You have no idea…then.
   A. what a hard time we had B. we had what a hard time
   C. that we had hard time D. what hard time we had
   [color=green]You are incorrect as an article is needed. A is correct.
   
6. Only a …of students attend those classes.
   A. little B. group C. band D.handful
   [color=green]You are correct.
   
7. Find the mistake in the sentence
   I’ve talked to the writer, the works of whom are popular with the youth.
   -> the work of whom
   [color=green]Typically of these old tests, that sentence sounds so stilted. I suppose the correct answer would be
   I’ve talked to the writer, the works of whom are popular with the youths.
   but native English speakers/writers would probably use:
   I’ve talked to the writer whose works are popular with the youths.