The hyphen is dying. It’s a sad fact, but since the beginning of the 20th Century, grammar books and style guides have been discouraging the use of the hyphen and even the Oxford English Dictionary has predicted its imminent extinction. So who knows just how long we have left with the hyphen as part of our punctuation family? For the time being however, the hyphen still remains (alongside the semi-colon) a somewhat troublesome member of the family. It’s overused by some and underused by many, and this brief guide aims to give you some friendly pointers as to when the hyphen is necessary in a sentence, and when its presence is perhaps not so welcome.

The OED defines principal purpose of the hyphen as to connect parts of a compound word, or parts of a word which have been previously divided. Simple examples of these include compounds such as “daughter-in-law”, “strong-willed” and with numbers like “twenty-eight”. These examples are common, but often words which are in fact not compounds are joined by a hyphen, such as “divorce lawyer” or “dinner date”.

Another instance where you’re likely to find the hyphen is between phrasal adjectives. You’ll find phrasal adjectives before a noun with two or more words being used to modify it. For example, the phrases “my long-lost sister”, and “razor-sharp talons” both use hyphenated phrasal adjectives. The hyphen would be removed however, if the noun were to precede the phrasal adjective: “the eagle’s talons were razor sharp” for example.

An exception to this rule would be in the use of phrasal adjectives which include “-ly” adverbs, as in “badly run business” or “sickly sweet feeling”. There are also some regular phrasal adjectives which will not require a hyphen. Take the phrase “civil rights movement” for example. In this instance, the phrasal adjective is so well known that there is no risk of ambiguity without employing a hyphen. With my previous example, however, if we saw the phrase “long-lost sister” without the hyphen, it could quite easily be misconstrued as my sister being both long, and lost.

Phrasal verbs, unlike most phrasal adjectives, also do not require a hyphen. Examples of these include “build up”, “break down”, and “stop off”. Only when these verbs are used as nouns does a hyphen become a necessary part of the structure (except in the case of “break down”, which becomes a whole new word in itself).

Finally, the hyphen can be used to add prefixes to pre-existing (there’s an example) words. It is important to note, however, that these are becoming much less common, with words such as “preschool” and “cooperate” taking precedence over their traditional forms. American English is also having an influence on our use of the hyphen, as the use of the hyphen in American English is much less common than it is on this side of the Atlantic.

With these rules in mind, a key word to remember when deciding on whether or not to use a hyphen is ambiguity. The primary purpose of the hyphen is to enhance the reader’s understanding of a passage, so if your good judgement suggests that using a hyphen will make a passage clearer, then chances are it’s worth using one. And as I was told throughout school and university, if you’re going to take a risk, then just make sure you’re consistent!