comma

 The trend these days is to use the comma as sparingly as form and clarity allow. But there are certain instances in which it should appear but all too often does not. Equally, it has a tendency to crop up with alarming regularity in places where it has no business. It is, in short, the most abused of punctuation marks and one of the worst offenders of any kind in the English language. Essentially the comma’s use is compulsory in three situations and recommended in a fourth.

 1. When the information provided is clearly parenthetical. Consider these two sentences, both of which are correctly punctuated: "Mr. Lawson, the energy secretary, was unavailable for comment"; "The ambassador, who arrived in Britain two days ago, yesterday met with the prime minister." In both sentences, the information between the commas is incidental to the main thought. You could remove it and the sentence would still make sense. In the following examples, the writer has failed to set off the parenthetical information. I have provided slashes (the proper name, incidentally, is virgules) to show where the commas should have gone: "British cars/says a survey/are more reliable than their foreign counterparts" (editorial in the Evening Standard); "Operating mainly from the presidential palace at Baabda/southeast of Beirut, Habib negotiated over a sixty-fiveday period" (Time magazine); "Mary Chatillon, director of the Massachusetts General Hospital’s Reading Language Disorder Unit/maintains: ‘It would simply appear to be.. .’" (Time magazine). It should perhaps be noted that failure to put in a comma is particularly common after a parenthesis, as here: "Mr. James Grant, executive director of the United Nations Children’s Fund (UNICEF)/says.. ." (Times).

 Occasionally the writer recognizes that the sentence contains a parenthetical thought but fails to discern just how much of the information is incidental, as here: "At nine she won a scholarship to Millfield, the private school, for bright children of the rich" (Evening Standard). If we removed what has been presented as parenthetical, the sentence would say: "At nine she won a scholarship to Millfield for bright children." There should be no comma after school, because the whole of the last statement is parenthetical.

 A rarer error is seen here: "But its big worry is the growing evidence that such ostentatious cars, the cheapest costs Ј55,240, are becoming socially unacceptable" (Times). When the incidental information could stand alone as a sentence, it needs to be set off with stronger punctuation - either dashes or parentheses.

 2. When the information is nonrestrictive. The problem here - which is really much the same as that discussed in the previous three paragraphs - is illustrated by this incorrectly punctuated sentence from the Daily Mail: "Cable TV would be socially divisive, the chairman of the BBC George Howard claimed last night." The writer has failed to understand the distinction between (1) "BBC chairman George Howard claimed last night" and (2) "The chairman of the BBC, George Howard, claimed last night." In (1), the name George Howard is essential to the sense of the sentence; it defines it. If we removed it, the sentence would say, "BBC chairman claimed last night." In (2), however, the name is nonrestrictive. In effect it is parenthetical. We could remove it without altering the sense of the sentence: "The chairman of the BBC claimed last night." When a name or title can be removed, it should be set off with commas. When it cannot be removed, the use of commas is wrong.

 Two hypothetical examples may help to clarify the distinction. Both are correctly punctuated. "John Fowles’s novel The Collector was a bestseller"; "John Fowles’s first novel, The Collector, was a bestseller." In the first example the name of the novel is restrictive because The Collector is only one of several novels by Fowles. In the second example it is nonrestrictive because only one novel can be the author’s first one. We could delete The Collector from the second example without spoiling the sense of the sentence, but not from the first.

 When something is the only one of its kind, it should be set off with commas; when it is only one of several, the use of commas is wrong. Thus these two sentences, both from The Times, are incorrect: "When the well-known British firm, Imperial Metal Industries, developed two new types of superconducting wires.. ."; "The writer in the American magazine, Horizon, was aware of this pretentiousness.. ." The first example would be correct only if Imperial Metal Industries were the only wellknown British firm, and the second would be correct only if Horizon were America’s only magazine. The same error in reverse occurs here: "Julie Christie knows that in the week her new film The Return of the Soldier has opened.. ." (Sunday Times). Since The Return of the Soldier was Julie Christie’s only new film of the week, it should have been set off with commas.

 The error frequently occurs when a marriage partner is named: "Mrs. Thatcher and her husband Denis left London yesterday" (Observer). Since Mrs. Thatcher has only one husband, it should be "and her husband, Denis, left London yesterday."

 3. With forms of address. When addressing people, you must use commas around the names or titles of those addressed. "Hit him Jim, hit him" (Sunday Times) should be "Hit him, Jim, hit him." The television program Good Morning America should really be Good Morning, America. The film I’m All Right Jack should have been I’m All Right, Jack. The lack of a comma or commas is always sloppy and occasionally ambiguous. In 1981, for instance, the Sunday Express illustrated a novel serialization with the heading "I’m choking Mr. Herriot" when what it meant was "I’m choking, Mr. Herriot" - quite another matter.

 4. With interpolated words or phrases. Words such as moreover, meanwhile, and nevertheless and phrases such as for instance and for example traditionally have taken commas, but the practice has become increasingly discretionary over the years. In Britain they have been more freely abandoned than in America; Fowler, for instance, seldom uses them. I would recommend using them when they suggest a pause or when ambiguity might result. This is especially true of however. Consider these two sentences: "However hard he tried, he failed"; "However, he tried hard, but failed." To keep from confusing the reader, if only momentarily, it is a good idea to set off however with commas when it is used as an interpolation. Much the same could be said of say: "She should choose a British government stock with [,] say [,] five years to run" (Daily Mail).