Affect is the verb. Effect is the noun
You affect things to cause effects.
Examples:
Her inability to take care of herself affected her health.
Her poor health was an effect of her inability to take care of herself.Note: when changing it into an adjective, you use the noun; it would be effective, not affective.

YOU ARE READING
Common Grammar Mistakes
RandomA collection of common grammar mistakes I run into in stories. I know this will probably not be read but I need somewhere to kind of vent.