Affect and Effect, which can be verbs or nouns, are often mixed up by English speakers because their meanings do overlap—and change in confusing ways between the noun and verb versions.
What I mean is that when you affect something, you create an effect. And when you effect something, you also create an effect in a different sense. But the noun affect means something completely unrelated to cause and effect.
Affect means “to make an impact on something, to change something, or make someone feel something”:
I hope the storm does not affect (change) our picnic plans.
The heat affects the molecules, making them separate.
He poetry is very affecting (creating feelings).
However, the change, impact, or feelings created are called effects, not affects. This is what confuses people:
The effect of the storm was to cancel our picnic.
The heat’s effect is to make the molecules move apart.
Her poetry has a great effect; it makes me feel one with all life.
It is best to digest this pair: when you affect something, you create effects. Because the other meanings (below) are quite different.
To effect means “to accomplish or make real”:
Obama effected a great change in American health care with the Affordable Care Act.
Democracy is supposed to effect the choices of its citizens, not only the rich ones.
The meaning of effect might seem close to affect, but it really is not. If Obama effected a change, that does not mean he had an impact on the change; it means he accomplished it. If we say Democracy effects the choices of its citizens, it does not mean that Democracy has an effect on their choices; it means that Democracy realizes (makes real) those choices.
Finally, there is the question of affect, the noun, a somewhat academic word that many Americans don’t even know, even though we see it within the word affection; affect, as a noun, means “emotion” and it is often positive or negative:
The subjects in our experiment reacted with positive affect to pictures of laughing babies.
Mental depression is associated with powerfully negative affect.
Affect as “emotion” refers to general states of feeling good (positive) or feeling bad (negative), not to more specific emotions, such as jealousy, shame, or humor.
As an adjective, affective refers to general emotional states:
The depressed subject’s terrible affective states made it difficult for him to sleep.
While effective refers to the accomplishment of effects:
Her design was quite effective; it really did the job.
So, affect and effect can be confusing for everybody, but it is not so much to remember. When you affect something, you cause an effect. When you effect something, you make it happen. And affect means “general emotional state.”
How to Use "Affect" in a Sentence
- It's true that she was affected by him in ways that were not always positive.
- He was unbearably affected by her death and he didn't know how to handle the situation.
- She tried to show as much affection as possible but it seemed to have no affect on him whatsoever.
- The fact that he never got any feedback from his boss affected his confidence.
- The amount of sugar in a person's diet affects their risk for obesity and diabetes.
How to Use "Effect" in a Sentence
- The effects of the drug are still unknown.
- This new law will have a major, yet unknown, effect on our society.
- The cold weather has a negative effect on my mood.
- On the whole, the effect is that the students prefer the new course.
- I do not know how long it will take, but I think the effect will be visible in about two weeks.
Questions About Common Phrases Using "Affect" and "Effect"
Here are some brief answers to common questions about how these words are used in common English phrases:
Is it "affect change" or "effect change?"
By far the most common usage is "effect change." To affect change has a logical meaning, but it's not the meaning most writers ans speakers have in mind when reaching for the phrase. See the above discussion on this page for a better understanding of these words' meanings and uses.
Is it "take effect" or "take affect"?
The correct phrase is "take effect." The phrase "take effect" has three meanings; it could be see as becoming operative, starting to work, or having its intended result. This phrase is often used in the context of law or business. Legislation might take effect on a given date, for example March 5th. The company's new policy will take effect on January 1st.
Is it negatively affect or effect?
The correct phrase is to negatively affect. To negatively affect means to have a negative impact or influence on something. For example, a lack of sleep can negatively affect a person's health.