The Semicolon

The semicolon (;) has only one major use. It is used to join two complete sentences into a single written sentence when all of the following conditions are met:

(1) The two sentences are felt to be too closely related to be separated by a full stop;

(2) There is no connecting word which would require a comma, such as and or but;

(3) The special conditions requiring a colon are absent.

Here is a famous example:

It was the best of times; it was the worst of times.

A semicolon can always, in principle, be replaced either by a full stop (yielding two separate sentences) or by the word and (possibly preceded by a joining comma). Thus Dickens might have written:

It was the best of times. It was the worst of times. or

It was the best of times, and it was the worst of times.

The use of the semicolon suggests that the writer sees the two smaller sentences as being more closely related than the average two consecutive sentences; preferring the semicolon to and often gives a more vivid sense of the relation between the two. But observe carefully: the semicolon must be both preceded by a complete sentence and followed by a complete sentence. Do not use the semicolon otherwise:

*I don't like him; not at all.

*In 1991 the music world was shaken by a tragic event; the death of Freddy Mercury.

*We've had streams of books on chaos theory; no fewer than twelve since 1988.

*After a long and bitter struggle; Derrida was awarded an honorary degree by Cambridge University.

These are all wrong, since the semicolon does not separate complete sentences. (The first and last of these should have only a bracketing comma, while the second and third meet the requirements for a colon and should have one.) Here are some further examples of correct use:

Tolkien published The Hobbit in 1937; the first volume of The Lord of the Rings followed in 1954.

The Cabernet Sauvignon grape predominates in the Bordeaux region; Pinot Noir holds sway in Burgundy; Syrah is largely confined to the Rhone valley.

Women's conversation is cooperative; men's is competitive.

If a suitable connecting word is used, then a joining comma is required, rather than a semicolon:

Women's conversation is cooperative, while men's is competitive.

A semicolon would be impossible in the last example, since the sequence after the comma is not a complete sentence.

Note, however, that certain connecting words do require a preceding semicolon. Chief among these are however, therefore, hence , thus, consequently, nevertheless and meanwhile:

Saturn was long thought to be the only ringed planet; however, this is now known not to be the case.

The two warring sides have refused to withdraw from the airport; consequently aid flights have had to be suspended.

Observe that in these examples the sequence after the semicolon does constitute a complete sentence. And note particularly that the word however must be separated by a semicolon (or a full stop) from a preceding complete sentence; this is a very common mistake.

There is one special circumstance in which a semicolon may be used to separate sequences which are not complete sentences. This occurs when a sentence has become so long and so full of commas that the reader can hardly be expected to follow it without some special marking. In this case, we sometimes find semicolons used instead of commas to mark the most important breaks in the sentence: such semicolons are effectively being used to mark places where the reader can pause to catch his breath. Consider the following example:

In Somalia, where the civil war still rages, western aid workers, in spite of frantic efforts, are unable to operate, and the people, starving, terrified and desperate, are flooding into neighbouring Ethiopia.

This sentence is perfectly punctuated, but the number of commas is somewhat alarming. In such a case, the comma marking the major break in the sentence may be replaced by a semicolon:

In Somalia, where the civil war still rages, western aid workers, in spite of frantic efforts, are unable to operate; and the people, starving, terrified and desperate, are flooding into neighbouring Ethiopia.

Such use of the semicolon as a kind of "super-comma" is not very appealing, and you should do your best to avoid it. If you find one of your sentences becoming dangerously long and full of commas, it is usually better to start over and rewrite it, perhaps as two separate sentences:

In Somalia, where the civil war still rages, western aid workers, in spite of frantic efforts, are unable to operate. Meanwhile the people, starving, terrified and desperate, are flooding into neighbouring Ethiopia.

In any case, don't get into the habit of using a semicolon (or anything else) merely to mark a breathing space. Your reader will be perfectly capable of doing his own breathing, providing your sentence is well punctuated; punctuation is an aid to understanding, not to respiration.

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