If you can tell the difference between a noun
and a verb, you'll be able to make the correct
choice between affect and
effect about 99% of
the time by simply applying the following
formula:
Now compare the following pair of correct
sentences using the formula above:
This news will probably affect
everyone.
This news will probably have an effect
on everyone.
In the first sentence above, a verb is used
to convey the meaning of influencing/impacting,
so only affect
would be correct for that sentence. But a
noun is definitely needed in the second sentence
due to its construction. Thus, according
to the formula, only effect
would be correct. It's safe to apply the
above formula to any sentence whereinfluencing
or impactingis involved. And
thankfully, 99% of effect/affect
sentences will express this type of meaning.
It's true: About 99% of the sentences
you'll write will be correct if affect
is your verb and effect
is your noun.
On those infrequent occasions when effect
is used as a verb, its meaning bears no
resemblance whatsoever to influencing/impacting.
The rare verb meaning of effect
is to bring about or place into
existence.
Examples of the rare usage of the verb effect
follow:
I once knew someone who said he could make
rain fall from a cloudless sky. He claimed
to have the ability to effect
rain.
The proponents of the new drug say that it
can effect headache relief
quickly.
Could a law banning handguns ever be effected
nationwide?