Sentence Correction

Guys,

Need clarification on the below points:

1. I read from Manhattan SC guide that "which" must refer the word immediately before it. But in non restrictive clauses when we use "which", does the same rule apply?

2. "One of the...." eg; one of the boys was/were???? This is always confusing for me. When the sentence starts with "one of the" and followed by plural subject. Do I need to use plural/singular verb???

Thanks in advance.

"One of the plural" - always is Singular.

Logical explanation -

First of all understand that in the expression "one of the noun", the noun is always PLURAL. e.g. you want to talk about a train. You will never say One of the train - since train is already one. If you say, "One of the trains", you will be correct.

Second, understand that you want to talk about just 1 train, that is why you are using the expression "one of the trains". This means your subject is Singular. And hence you will use singular verb form.

I hope this makes sense.

As far as your first question goes, I believe the answer is YES. Which always refers to the noun preceding it. In the case of non-restrictive clause, which will modify the noun right before the comma.