It’s time to talk about AFFECT and EFFECT. Yes, yes, I know it’s easy to confuse a verb and noun—if you’re learning the language, but this offense occurs regularly by native English speakers and writers, so I must intervene.
Here’s the boring—but necessary—stuff:
AFFECT: it’s a VERB, which means it shows ACTION; for example, “I know this will AFFECT your image in a positive way.”
EFFECT: it’s a NOUN, which means it MUST be a person, place, thing, idea, or concept; for example, “The greenhouse EFFECT is overblown, according to some.”
The quick and dirty of this lesson: if you can’t remember the difference between a noun and a verb, just use association: Action=Affect.
Now, go write.