The AP Styleguide section on usage explains the use of and difference between words. It is organized alphabetically, like a dictionary. Examples include affect/effect or indiscreet/indiscrete, or general information, such as the full name of the Girl Scouts or the definition of Freddie Mac.
Affect can be a verb meaning to influence. (common usage)
The committee's opinion affected the decision of the CEO.
Affect can be a verb meaning to pretend to have a feeling.
He affected concern for the victims of COVID-19.
Affect can be a noun when use in psychology referring to feelings or emotions. Not recommended.
Affect is pronounced AH-fect when referring to anything emotional.
Effect can be a verb meaning to cause.
The virus effected the closure of public spaces.
Effect can be a noun meaning the result. (common usage)
The effect of the gathering was the death of a dozen people.
Among is used with more than two items.
The voters chose among the many candidates.
Between is used with two items.
The voters chose between the two candidates.
Discreet means careful or inconspicuous.
They asked that the police investigate be discreet.
Discrete means separate or distinct.
My life is divided into discrete parts: private, professional, and community,
Farther refers to a physical, measurable distance.
They were pleased that their destination was only five miles farther.
Further refers to a figurative distance.
You will find the link further down in this e-mail.
That misconception couldn't be further from the truth.
Further is also a verb meaning to aid or to advance.
The promotion would further his long-term goals of corporate leadership.
After I earn a bachelor's degree, I intend to further my education in graduate school.
Fewer means "less than," and is used for individual, discrete, countable objects.
You gave him five cookies at snack time? Please give him fewer next time.
Less means "not as much," and is is used for an uncountable quantity not made up of individual, discrete objects.
She put forth less effort as she learned the job.
Lay/laid/had laid/Laying are verb tenses meaning to place or put something and that take a direct object.
I asked the assistant to lay the suitcase on the bed. [The suitcase is the direct object after the verb.]
She then laid it on the bed and left the room. [It is the pronoun and the direct object after the verb.]
Lie/lied/had lied/Lying are verb tenses meaning to make an untrue statement.
I do not like to lie as a rule; it's too much trouble to remember the lies.
He lied so often that people assumed he was always lying.
Lie/lay/had lain/Lying are verb tenses meaning to recline, but does not take a direct object.
Please lie back and relax.
He felt dizzy, so he lay back and went to his happy place.
He felt been feeling nauseous, so he had lain lay back and focused on his breath.
| to lay | to lie | to lie [down] | |
| Meaning | to put or place [something, direct object] | to make an untrue statement | to recline |
| Present tense | lay(s) [something, direct object] | lie(s) | lie(s) |
| Present participle | was laying [something, direct object] | lying | was lying |
| Past tense | laid [something, direct object] | lied | lay |
| Past participle | had laid [something, direct object] | had lied | had lain |
| Future tense | will lay [something, direct object] | will lie | will lie |
Mnemonic definition aid: Lay is when you place something, but lie is when you recline.