Question: Not sure if I used affect/effect correctly, but anyway...

So, here's my question if the title didn't explain it well enough: say you have the following phrase: "in the men's bathroom". The plural of "man" is "men", so when showing possession with a plural word that doesn't end in "s", you use "apostrophe s", right? Well, what if "bathroom" were also plural? So you've got multiple men and multiple bathrooms. Would it be "men's bathrooms" or "mens' bathrooms"? Does the object being possessed being singular or plural make a difference as far as whether or not you use 's or s'? I could have sworn I was taught in school it does make a difference, but now I can't remember.

Answer: 
It is men's bathrooms, never mens' ([Mens' or Men's?](http://crofsblogs.typepad.com/english/2007/07/mens-or-mens.html).)

There is no difference in the noun-number of the object being possessed (whether it is singular or plural). This link may be helpful: [Rules for Apostrophes explaining possession](http://www.grammarbook.com/punctuation/apostro.asp).
This is two different questions:

**Number 1:**

No. The possessive noun does not effect the possessed.

**Examples:**

Men: singular; Bathroom: plural:

> 
> the man's bathrooms
> 
> 
> 

Men: plural; Bathroom: plural:

> 
> the mens' bathrooms
> 
> 
> 

Men: singular; Bathroom: singular:

> 
> the man's bathroom
> 
> 
> 

Men: plural; Bathroom: singular:

> 
> the mens' bathroom
> 
> 
> 

However, the above is wrong, because men is an irregular noun. for most nouns, the above, however, for men, the below is true:

Men: singular; Bathroom: plural:

> 
> the man's bathrooms
> 
> 
> 

Men: plural; Bathroom: plural:

> 
> the men's bathrooms
> 
> 
> 

Men: singular; Bathroom: singular:

> 
> the man's bathroom
> 
> 
> 

Men: plural; Bathroom: singular:

> 
> the men's bathroom
> 
> 
>