A few weeks ago I saw an advertisement on TV which showed a dentist recommending a brand of toothpaste, and the patient coming to the doctor afterwards saying “less germs". That was a cue for me to look at the use of “less" in that expression. One of the basic rules of grammar says, use “less" for quantity and amount, and use “fewer" for countable things. The patient should have said, “fewer germs". Less is used with things that cannot be counted. “There is less communication between the two sides today." When referring to money, less is preferred. “He earns less than Rs50 a day."

Most of the lists begin with affect/effect, which seems to be a sort of acid test for writers. “Affect" means to influence, generally for bad. “Such habits will affect your health." “Effect" (noun) means “result". Effect (verb) means to cause, to bring about. “The election commission effected a few changes in the voting schedule."

A recent headline in a national daily said: “Afghan soldier kills two Nato troops." The expression “two troops" jarred on my ears. Troop is a collective noun and two troops can be two groups or units of soldiers. We can eschew this ambiguity by using troops with large numbers, and avoiding it with small numbers. “Ten thousand troops" sounds all right, but “two troops" doesn’t.

A similar question arises with “persons" and “people". Stylebooks now recommend “people" for all plural uses. That includes “two people".

“Biweekly" is a little word that sits there in the dictionary and seems to challenge you with its ambiguity. Most dictionaries give two very different meanings: first, twice a week, as in “biweekly flights", and second, “once in two weeks", as in a “biweekly publication". Some writers suggest semi-monthly as an alternative to biweekly in one of its meanings.

Ludo is a popular British board game. This Latin word means “I play". There are a dozen words with the Latin root, lud, and two of them are likely to get confused: “allude" and “elude". To allude means to refer to something without naming it. “The MP was alluding to the disappearance of important files from the office." “Elude" means to avoid or evade. “After the jailbreak, the thief has eluded the police for a month now."

Refute is often wrongly used as a synonym for deny. In a debate you rebut an argument by speaking against it or contradicting it. But to refute an argument, you have to successfully prove that it is wrong. “The minister refuted the charges made by the opposition." To deny something means to say that it is not true. “The minister denied that he had a secret meeting with the insurgents." A rebuff is a sharp and blunt response to an offer.

Comprise, compose, consist and constitute are best learnt together. They are near-synonyms using different structures. Any use of comprise with the preposition “of" is wrong.

A word that people misuse out of over-enthusiasm is “literally". “After hearing the news he was literally floating on air." You can use literally here only if the person referred to is a master of levitation.

The wealth of the English vocabulary comes to us at a price. Similar sounding and similar looking words can confuse us. But words are the toys we adults play with, and each day brings a new discovery: that noisome has nothing to do with noise, that bemuse has nothing to do with amuse, that apparent has two opposite meanings.

V.R. Narayanaswami is a former professor of English, and has written several books and articles on the usage of the language. He looks at the peculiarities of business and popular English usage in his fortnightly column.

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