When do you use affect and when do you use effect?

It's a good question. When do you use affect, and when do you use effect? What is the difference between the two? Is there a difference?

There is definitely a difference between the two words; otherwise, there would be no need to have two different forms of the same idea. Let's take a look at two situations:

In the first example, affect is implying an action. The lemon juice is affecting flavor. It is doing something to the dish. In this sentence, affect is being used as a verb. In the second example, effect is more of an object, a thing that is being discussed. In this sentence, effect is being used as a noun. And, we can also verify this by noticing the article that comes before effect: a. Articles (a, an, and the) will come right before nouns or noun phrases.

So, what is the difference between affect and effect? Basically, it all comes down to what part of speech it assumes in the sentence. If it's a verb, use affect; if it's a noun, use effect.

Now, that's fine, but it's highly likely that you may forget which one is the verb form and which one is the noun form. I like to tell my students to remember this little mnemonic: think a for action.

You can even apply this mnemonic to other confusing word pairs. For example, we can take a look at the words accept and except. If we use the rule a for action then we would probably label accept as the verb (the action). That would be correct. Accept is the verb form, and except is another form, in this case, a preposition meaning excluded from the rest of the group. Let's take a look at a couple examples:

So, hopefully, this helps you with determining when to use affect and when to use effect. It's as simple as verb vs. noun.