possessive

Anonymous

Hi,

1. ... is a girls' subject  OR is a girl's subject

2. ... is a girls' school

3. ... is a teachers seminar. ... is a teachers' seminar [a seminar for teachers] 

4. ... is a games magazine .

As to no. 3, why is it that I rarely see 'a teachers' seminar'? I think Mr. M told us that a publisher dislikes an apostrophe for that kind of case. In my view, it should have an apostrophe.

As to no. 4, why is that 'games' instead of 'game' is used? Since a magazine is for many games, then the plural 'games' is OK. I thought a singular version? is usually used as an adjective?   In the UK a "game magazine" would be interpreted as being about animals or birds such as deer, pheasants, grouse and so on.