A reader asked me to define these two words and explain how to use them. They're closely related words, very similarly spelled and pronounced, so it's easy to see why people get them confused. Affect is the verb, the action word. "The tragic story affected him deeply." Effect is the result. It's the noun, the thing. "The tragic story had a powerful effect on him." Perhaps it would help to think of the word effective. Something is effective if it has an effect. Unfortunately, and to make things more confusing, there are a couple of cases where the situation is reversed. Effect does have one use as a verb: to bring something about, to cause something to happen. "The prisoner effected his escape by jumping from the police car." And affect has one use as a noun, meaning one's mental state. Fortunately, both of these uses are rare in ordinary English. Affect can also be used as a verb in the sense of "pretend": "He affected an air of cynicism." I think that use is rather old fashioned, though. I hope the effect of all of this is to leave you less confused, rather than more.
(Will be published in the July 2010 issue of Denver's Community News.)
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