Page 390 - Practical English Usage 3ed - Michael Swan, Oxford

noun + noun (2): advanced points 386
6 pronunciation
Most noun + noun combinations have the main stress on the first noun. a 'bicycle factory a 'fruit drink 'ski boots 'coffee beans
However, there are quite a number of exceptions.
a garden 'chair a fruit 'pie
The difference between noun modifiers and adjectival modifiers is sometimes shown by stress. Compare:
a 'French teacher (noun modifier: a person who teaches French)
a French 'teacher (adjective modifier: a teacher who is French)
To be sure of the stress on a particular combination, it is necessary to check in a good dictionary.
For the stressing of road and street names. see 502. 7 spelling
Some short, common noun + noun combinations are generally written together like single words.
bathroom lampshade seaside (BUT NOT Fttilwttysmfttm)
Others may be written with a hyphen (e.g. letter-box) or separately (e.g. furniture shop). In many cases usage varies, and some combinations can be found written in all three ways (e.g. bookshop, book-shop or book shop). Hyphens are becoming less common in modem English, and (except with very common short combinations like bathroom) it is usually acceptable to write the two words separately.
For more information about the spelling of different kinds of compounds. see 559.
For information about the spelling of particular noun + noun expressions. see a good dictionary.
386 noun + noun (2): advanced points 1 classifying expressions: a sheepdog
The noun + noun structure is mostly used to make 'classifying' expressions. which name a particular kind of thing.
mountain plants (a special group of plants) mineral water (a sort of water)
a sheepdog (a particular kind of dog)
We use noun + noun especially to talk about things that belong to common well-known classes (so that the two nouns really describe a single idea). In other cases we prefer a preposition structure. Compare:
the postman, the milkman, the insurance man (all well-known kinds of people who may call regularly at a British home)
a man from the health department (not a regular kind of visitor) More examples:
- He was reading a history book. (a common class of book)
He was reading a book about the moon. (NOT a rltBt312 bBBk)
- Size was sitting at a corner table in the restaurant. (Restaurants often have
comer tables.)
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