'ONE OF' Constructions: What is the simplest way?

[zaarathelab]

Ok so I always get confused with the 'one of' constructions. Can you guys pls provide a definitive rule for this construction?

Here are some examples -

1. Since 1989, after the Berlin Wall had been demolished, one of the most problematic ethnic groups in the reunified Germany, in cultural and economic assimilation terms, were the former East Germans, who have had to acclimate to an entirely different political system.

Here the construction is 'one of...groups' - OA suggests that this is singular

2. A higher interest rate is only one of the factors, albeit an important one, that keeps the housing market from spiraling out of control, like it did earlier in the decade.

Here the construction is 'one of...factors' - OA suggests that the verb should be keep, suggesting that one of is plural?

Also I read somewhere that 'ONE OF CONSTRUCTIONS' FOLLOW THE SANAM PRONOUN RULE -Some, Any, None, All, More/Most and they take on singular forms only in the following cases -

He is the only one of the my friends who is an IT professional

He is one of my friends who are IT professionals

One of my friends is an IT professional

IS 'ONE OF' CONSTRUCTION CONTEXTUAL?

Pls help!!!

[RonPurewal]

this is the wrong folder for this question; this folder is for GMAT PREP SOFTWARE questions only. therefore, this thread is now locked and will be deleted in about a week.

i covered this topic on another forum here:
http://www.beatthegmat.com/one-of-the-t ... tml#174075

that's a pretty complete treatment. however, if you still have questions, please start a new thread *in the right folder* (= either the GENERAL VERBAL or MGMAT VERBAL folder, depending on where this problem comes from). thanks.