Study the information about compound nouns.
Compound nouns are words for people, animals, places, things, or ideas, made up of two or more words.
Most compound nouns are made with nouns that have been modified by adjectives or other nouns.

1. We can make compound nouns with the -ing form: dancing-shoes.

2. The -ing form can sometimes be an adjective:

Can you see that wonderful dancing couple? (= couple that is dancing)

3. The -ing form can be the first part of a compound noun:

I want to buy a pair of dancing-shoes.
4. Names of materials and substances (gold, leather) are like adjectives. We can use them to form compound nouns.

A watch made of gold - a gold watch

These words remain nouns because they do not have comparative and superlative forms.

She can’t buy this gold watch.

5. There are two exceptions: wool and wood. They have adjectival forms:

A table made of wood - a wooden table

A sweater made of wool - a woollen sweater
6. There are adjectival forms of words like gold:

Glass - glassy
Gold - golden
Silver - silvery
Silk - silky - sliken
Steel - steely  
Stone - stony