Compound adjective
When two or more words come before the noun they modify, they form a compound adjective. They are usually connected by a hyphen.
E.g.
1. Number+noun.
A 3-year-old boy — Un niño de 3 años= (A 3-years-old boy, A boy of 3 years)
A thousand-word article — Un artículo de mil palabras
2.Adjective+ Past participle/ noun+ed.
A white-haired man — Un hombre de pelo blanco ( a white hair man)
A big-eared cat — Un gato de orejas grandes
3.Noun+ Present participle(ing).
A thrill-seeking man — Un hombre que busca emociones fuertes
A man-eating monster — Un mostruo que come carne humana
4. Phrase
A slit-your-wrists type story— Un cuento para cortarse las venas
A faster-than-usual pace— Un ritmo más rápido de lo habitual
A once-in-a-lifetime chance— Una oportunidad única en la vida