Please give me a two hour leave
Please give me two hours leave
Providing that those are correct, Could you tell me when/ in which situation you would rather use one over the other?
Meanwhile, would you tell me if I have well rephrased number 1?
a two hour(long) leave
When you form adjectives from numbers there are two factors to bear in mind:
- Number adjectives are always hyphenated:
- Unlike in other languages, English adjectives are never pluralized. By way of contrast, in Spanish the adjective ciego blind (person), can be made plural ciegos blind (people). Not so in English - so much so that even the counted element in a numerical adjective takes a singular form:
two hours ➝ two-hour
three miles ➝ three-mile
five years old ➝ five-year-old