Punctuation

Hyphens in compound words

 
Hyphens (-) are used to link words and its parts. We have three major scenarios where it is used-

Hyphens are used in compound words to show combined meaning of its component words, for example- (Father-in-law, bad-hearted). It also shows relationship between the words that make up the sentence. We don't need to use this in every compound word, for example forty-eight.

Compound Adjectives-

It's made up of (a noun + an adjectives), (a noun+ a participle), (an adjective+ a participle). For the sake of better understanding, read the examples below-

noun + adjective	noun + participle	adjective + participle
accident-prone	computer-aided	good-looking
sugar-free	power-driven	quick-thinking
carbon-neutral	user-generated	bad-tempered
sport-mad	custom-built	fair-haired
camera-ready	muddle-headed	open-mouthed

You should always use hyphen when the compound comes before noun- e.g. (well-known, up-to-date) and when compound comes after the noun you shouldn't use the hyphen.

It is significant to use hyphen in compound adjectives describing the ages and lengths. Leaving them out can make the meaning ambiguous. E.g. 100year old trees

Compound verbs-

Use a hyphen when a compound formed from two nouns is made into a verb, e.g.:

noun	verb
an ice skate	to ice-skate
a booby trap	to booby-trap
a spot check	to spot-check
a court martial	to court-martial

 

Phrasal verbs 

You should NOT put a hyphen within phrasal verbs - verbs made up of a main verb and an adverb or preposition. For example: 

Phrasal verb	Example
build up	You should continue to build up your pension.
break in	They broke in by forcing a lock on the door.
stop off	We stopped off in Hawaii on the way home.

If a phrasal verb is made into a noun, though, you SHOULD use a hyphen:

Noun	Example
build-up	There was a build-up of traffic on the ring road.
break-in	The house was unoccupied at the time of the break-in.
stop-off	We knew there would be a stop-off in Singapore for refueling.

  

Compound nouns 

A compound noun is one consisting of two component nouns. In principle, such nouns can be written in one of three different ways:

one word	two words	hyphenated
aircrew	air crew	air-crew
playgroup	play group	play-group
chatroom	chat room	chat-room

In the past, these types of compounds were usually hyphenated, but the situation is different today. The tendency is now to write them as either one word or two separate words. However, the most important thing to note is that you should choose one style and stick to it within a piece of writing. Don’t refer to a playgroup in one paragraph and a play-group in another.

Hyphens to join prefixes to other words 

Hyphens can be used to join a prefix to another word, especially if the prefix ends in a vowel and the other word also begins with one (e.g. pre-eminent or co-own). This use is less common than it used to be, though, and one-word forms are becoming more usual (e.g. prearrange or cooperate).

Use a hyphen to separate a prefix from a name or date, e.g. post-Aristotelian or pre-1900. 

Use a hyphen to avoid confusion with another word: for example, to distinguish re-cover (= provide something with a new cover) from recover (= get well again).

 Hyphens to show word breaks 

Hyphens can also be used to divide words that are not usually hyphenated. 

They show where a word is to be divided at the end of a line of writing. Always try to split the word in a sensible place, so that the first part does not mislead the reader: for example, hel-met not he-lmet; dis-abled not disa-bled. 

Hyphens are also used to stand for a common second element in all but the last word of a list, e.g.:

You may see a yield that is two-, three-, or fourfold.