singular or plural?

[vil]

Dear teachers,

Would you be kind enough to explain to me the authoritative grammatical rule concerning the expression in bold in the following excerpt from an English text?

“Measures of another kind that can also be employed by the Secretary Council are the operations of the UN peace-keeping armed forces and military observer missions.

There is a plural in my native language also by the substantive “military obsevers”.

Thank you for your efforts.

Regards,

V.

[siegfried_rus]

“Measures of another kind that can also be employed by the Secretary Council are the operations of the UN peace-keeping armed forces and military observer missions.

V.

It's about observer missions rather than military observers in this instance, as far as grammatical interdependencies are concerned. Thus, observer here is used attributively.

Good luck, vil!

[vil]

Hi siegfried_rus,

Thank you for your reply as well as for your excellent explanation.

As you probably know, the similarly grammatical rule applies to following cases too: two-mile race, three-hour interval, twelve-question show, sixty-four dollar quiz?

Thank you again for your backing.

Regards,

V.

[siegfried_rus]

Hi siegfried_rus,

Thank you for your reply as well as for your excellent explanation.

As you probably know, the similarly grammatical rule applies to following cases too: two-mile race, three-hour interval, twelve-question show, sixty-four dollar quiz?

Thank you again for your backing.

Regards,

V.

You are welcome, vil!

We seem to coincide in our focus on grammar theory, that's perhaps why it so happened that most of my choice questions to answer have so far been yours. In a foreign language, each time I come across an uknown, or even vague, case, I can't go further until I've made inquiries to learn and understand it...

Re your examples: it seems you hit it on the nail!

Regards,
Vladimir