Տեսություն

Adjective building
Some adjectives are formed by joining two or more words with a hyphen between them to show that it is one adjective. They are called compound adjectives.
Օրինակ
green-eyed, long-haired
Compound adjectives are formed in many ways:
  
adjective + noun + ed                                               long-haired, green-eyed                           
adjective + verb + inggood-looking, fast-talking
adjective + nounhigh-quality, low-fat
noun + adjective
world-famous, sugar-free, ice-cold 
noun + nounpart-time
noun + present participlemouth-washing, English-speaking
noun + past participlesun-dried, hand-made
adverb + past participlewell-known, densely-populated  
adverb + verb + ingrapidly-growing, hard-working
number + nounten-dollar, one-way
 
If and is possible to use between the two words, then a hyphen isn't necessary.
Օրինակ
She has a big blue book. (She has a big and blue book.)
Use a hyphen when the compound adjective comes before the noun it modifies, but not when it comes after the noun.
Օրինակ
It was quite a thought-provoking book.