Verbal Ability nouns and pronouns

Question

Whether these sentences are correct or not

1> Each of the five men received a reward.

2> The boy narrated stories each.

3> Each of the members had his own opinion about the task.

4> Either the engineer or his mechanics failed in his duty.

Answer 1

Only 1 seems correct.

4 is wrong because in the context of the sentence, it should be "their duty" and not "his duty".
3 is wrong because it should be member, not members.
2 is wrong because it isn't a coherent sentence.

EDIT:
To fix it:

2. boys
3. their
4. their

Comments

In the third sentence, you are saying that member comes but according to rule after "of + the" Noun should be plural because I am talking about all members and not a single member otherwise it is meaningless to say each of the member because my member is only one

 

In the fourth sentence, I am talking to anyone from engineer or mechanics not both of them so it must take his instead of their

 

Please tell me if I am wrong