1

Which is correct, a "two-year" program or "two-years" program?

The difference between two expressions is the absence/presence of "s", i.e., singular or plural.

Nathan Tuggy
  • 9,432
  • 20
  • 39
  • 56
T_T
  • 471
  • 1
  • 5
  • 12

2 Answers2

6

When we use counted elements as adjectives, they take a hyphen and lose the plural ending -s, because adjectives don't have plural forms in English:

Here are some examples:

a two-year program, a 3-day hike, a two-hour test, a four-year-old child, a 100-year war

Alan Carmack
  • 11,839
  • 2
  • 22
  • 52
Violette
  • 655
  • 6
  • 8
  • 1
    Yes, but we do actually have *[The hundreds year war](http://www.history.com/topics/hundred-years-war)* and this is because two hundred years ago, English speakers did use *plural forms* of this kind of expression, as in a *five-feet long* piece of lumber. You'll find these in 19th century novels, for example. Basically, it is whatever usage is popular at some given point in time, as usages are always changing. – Alan Carmack May 03 '16 at 07:19
  • 1
    @AlanCarmack Agree with your comment, except that you misplaced the s in _Hundred Years War._ https://books.google.com/ngrams/graph?content=hundreds+year+war%2Chundred+years+war%2Chundred+year+war&case_insensitive=on&year_start=1800&year_end=2008&corpus=15&smoothing=3&share=&direct_url=t4%3B%2Chundred%20years%20war%3B%2Cc0%3B%2Cs0%3B%3BHundred%20Years%20War%3B%2Cc0%3B%3BHUNDRED%20YEARS%20WAR%3B%2Cc0%3B%3Bhundred%20years%20war%3B%2Cc0%3B%3BHundred%20Years%20war%3B%2Cc0%3B.t4%3B%2Chundred%20year%20war%3B%2Cc0%3B%2Cs0%3B%3BHundred%20Year%20War%3B%2Cc0%3B%3Bhundred%20year%20war%3B%2Cc0 – Adam Mar 28 '17 at 17:03
1

In compound adjectives that contain a noun no plural-s is used, eg a ten-year-old boy. http://www.espressoenglish.net/compound-adjectives-in-english/

rogermue
  • 8,418
  • 2
  • 22
  • 24