The easiest way to distinguish between affect and effect is to think of affect as a verb (doing word) and effect as a noun (naming word). Unfortunately, there are a couple of exceptions.
Affect means to influence.
The weather affected the outcome of the Grand Prix.
Affect is usually a verb.
Occasionally affect is a noun when used in a psychological context to mean feeling or emotion.
Effect means result or outcome. It is usually a noun.
The effect was dramatic.
Occasionally effect is used as a verb, meaning to cause or bring about a result.
To effect a sale.
affect and effect
The thunderstorm affected my mood, but I used an umbrella so the rain had no effect on my hair-do.
Because many people confuse affect and effect, some people use impact instead of effect.
The storm affected my mood, but I used an umbrella so the rain had no impact on my hair-do.
A memory jog
Grammar Girl suggests thinking of a raven to help you remember the difference. Raven has the letters AVEN in it, which stand for affect-verb-effect-noun.
Learn more about other commonly confused words with my online Business Writing course.
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