The hyphen ( - ) is used
a) to divide words of at least two syllables which will not fit at the end of a line; the hyphen indicates that the word is continued on the next line. Make sure that each part of the divided word has at least two letters.
b) to show that certain compound words function as a single word. Be sure to always check the dictionary if in doubt.
Compound adjective (preceding a noun): double-jointed
Compound noun: head-hunter
Compound verb: kick-boxing
c) with certain combination words. Be sure to check your dictionary.
d) with certain numbers and fractions.
1) Use a hyphen to spell out numbers from twenty-one to ninety-nine.
2) Use a hyphen to spell out a fraction when used as an adjective; hyphenation is not required when the fraction is used as a noun.
Adjective: one-quarter full
Noun: The container had one quarter of the liquid.
e) in certain prefixes and suffixes.
1) Hyphenate a prefix with a capitalized base word: un-American
2) Hyphenate a prefix with a date: pre-1600
3) Hyphenate a single-letter prefix: x-ray
4) Use a hyphen with all-, ex-, self-, and -elect: all-knowing; ex-husband;
5) Use a hyphen to separate an awkward combination of letters: fall-like.
6) Use a hyphen to differentiate between homonyms:
Recover - to get back; to regain
Re-cover - to cover again
More punctuation guides
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