7 Grammar Rules That Everyone Should Learn

Who needs good grammar anyway?  Grammar rules are so boring to learn and totally pointless! Isn’t it good enough that people can understand what you’re trying to say?

But wait! Did you know that having good grammar increases your chances for finding love? And knowing proper grammar rules can mean the difference between a well-paying job and, well, no job at all. Like it or not, people judge you based on your grammar use (especially if you’re terrible at it). Speaking or writing without the proper use of grammar rules can make you come across as uneducated and unreliable. I don’t care if you have your PhD or if you’re a musical prodigy!

What if I had started this blog post by writing, “Hey everyone wha’ts up? Hears a post for all of you if your interested in lerning about how to right using good grammar lets get starting!”

You’d likely hit the back button as quickly as possible. Thanks to poor grammar in this sentence, my message has become untrustworthy. That sentence may be a bit of an exaggeration, but from my experience editing papers at Kibin, I know for a fact that bad grammar like this happens. And it happens a lot.

Grammar is a vast topic. To narrow it down, I asked some of the other Kibin editors to tell me about their top grammar peeves. Let’s get started!

Grammar Rules You Should Learn #1: The Difference Between Affect and Effect

Peeve submitted by Naomi T. (that’s me)

“The special effects in that movie really affected me!”

I must admit that I was once guilty of mixing these two words up too. But, now that I know the difference, the misuse of affect and effect really affects me poorly. In other words, it drives me crazy.

Let’s settle the score on the difference between affect and effect once and for all.

Effect is a noun. (Remember, a noun is a person, place or thing.)

Here are some examples of effect in a sentence:

  • Good example“The special effects were amazing.”
  • Good example“I appreciate the beneficial effects of modern medicine.”
  • Good example“The effect of working too hard is exhaustion.”

helpful hintHelpful Hint: Any time you can write the word the before the word effect, you know you’re dealing with a noun. I learned to remember that effect was a noun because effect starts with the letter e and the ends with the letter e. The effect of this is that I always know which one is the noun form.

Affect is a verb. (Remember, a verb is an action word, as in to affect)

Here are some examples of affect in a sentence:

  • Good example“The sad plot affected me.”
  • Good example“A lot of people have been affected by cancer.”
  • Good example“Climate change affects everyone.”
  • Good example“The special effects affect my epilepsy.”
  • Good example“An excellent speech can affect great change.”

Also confusing is that the words affective and effective are both adjectives. So what’s the difference between them?

Affective relates to how things generate or derive from emotions. It’s a mushy-gushy word.

Good example“The doctor’s affective approach made her patients feel like they were in good care.”

Effective relates to the ability to produce positive results.

Good example“The doctor’s effective treatment cured her patient.”

If you need more help, visit Grammar Girl (my favorite grammarian), who teaches the difference between affect and effect while wielding an Aardvark. For serious.

Grammar Rules You Should Learn #2: The Difference Between Witch, Which, and That

Peeve submitted by Crystal W.

“Wait, which witch is that witch?”

Crystal admits to being quite a stickler when it comes to good grammar. When I asked her which broken grammar rules upset her most, she said, “ALL grammar mistakes make me crazy!” I guess it’s good that she’s a Kibin editor!

First, let’s get the easy one out of the way. A witch, in fairy tales, at least, is a woman with the power of black magic, such as the Wicked Witch of the West in the Wizard of Oz.

helpful hintHelpful Hint: Never call a witch a “which,” or she’ll turn you into a toad.

grammar rules witch which

Okay, since that’s cleared up, let’s chat for a moment about the difference between which and that.

Consider these two sentences:

Good example“Witch covens, which use broomsticks, can fly.”

Good example“Witch covens that use broomsticks can fly.”

The difference in meaning between these two sentences may be subtle, but it’s important. Which adds additional information to the sentence in the form of a nonrestrictive clause. All that means is that the information it adds does not change the meaning of the sentence. In this example, “which use broomsticks” lets us know that these witch covens happen to have broomsticks. But all witches can fly, with or without broomsticks. “Witch covens can fly” is the essential part of the sentence.

The word that limits the information in our sentence using a restrictive clause. In other words, the meaning of the sentence would completely change if we removed the restrictive clause. In this sentence, “that use broomsticks” is essential to the sentence. It means that the witches actually require broomsticks to fly. Without their broomsticks, they are destined to walk everywhere, or take the bus.

Use which when you are adding information about something and that when you are limiting information about something. Also, it’s grammatically correct to place a comma before the word which.

If you need more help, visit this lesson on the difference between which and that.

Grammar Rules You Should Learn #3: The Difference Between It’s and Its, and Other Problems of Possession

Peeve submitted by Naomi T.

“My car is stuck. It’s too cold outside, so its engine won’t start.”

Do you think possession is something that only happens in movies? It’s not. We use grammatical rules to demonstrate the possessive every day.

grammar rules possessive

In general, possessive nouns allow you to describe what belongs to whom, but in a shorter way. (There are exceptions to this rule that I’m not going to dig into here, but if you’re curious, read why possessives are not always about possession.)

Possessives are very convenient. I could really waste the limit on my Twitter feed by writing, “The car of my boyfriend broke down,” and sound kind of weird while I do it. Or I could save some characters and avoid sounding like an alien by writing, “My boyfriend’s car broke down.”

Typically the rule of thumb is to include an apostrophe and the letter s (‘s) after a singular noun, or after a plural noun that doesn’t end in an s.

For example:

  • Good example“The child’s toy” (Child is a singular noun.)
  • Good example“The children’s toys” (Children is a plural noun not ending in an s.)
  • Good example“The cat’s food” (Cat is a singular noun.)

If your plural noun ends with an s, just add an apostrophe. For example:

  • Good example“The cats’ food” (Cats is a plural noun.)
  • Good example“The airplanes’ fuel” (Airplanes is a plural noun.)
  • Good example“Parents’ night out” (Parents is a plural noun.)

One major (and often confusing) exception to this rule is when you use the possessive form of the pronoun it.

At first glance, it would seem that the possessive form would have an apostrophe, it’s, but it doesn’t. In fact, the possessive form of it is its.

Good example“I helped the dog find its bone.” (Dog is a singular noun, and its is a singular possessive pronoun).

Good example“When I found the toy truck, its wheel was broken.” (Toy truck is a singular noun, and its is a singular possessive pronoun).

It’s, on the other hand, is the contraction of it and is, or it and has.

Good example“It’s cold outside.” (It is cold outside.)

Good example“It’s been a tough year.” (It has been a tough year.)

If you need more help, check out this helpful lesson on possessives.

Grammar Rules You Should Learn #4: The Difference Between Well and Good

Peeve submitted by Travis B.

“It’s a good habit to eat well.”

Travis is the fearless leader of Kibin, and while he usually leaves the editing up to his loyal legion of editors, he has spent many a night into the wee hours fixing school essays and important business documents. His grammar rule pet peeve? Misusing the words well and good.

Let’s not upset the boss man and get this rule straight right now.

grammar rules well and good

helpful hintHelpful HintHere is the main difference between these two well-meaning words. Good is an adjective, which means it modifies a noun. Well is an adverb, which means it modifies a verb.

So it’s good when you write:

Good example“He’s a good boy.”

In this sentence, good describes the noun, boy.

Good example“The pie tastes good.”

In this sentence, good describes the noun, pie.

And you’re doing well when you write:

Good example“The steak was well cooked.”

In this sentence, well describes the verb, cooked.

Good example“He’s doing well in school.”

In this sentence, well describes the verb, doing.

Also note that well is a synonym for healthy, so you’d write:

  • Good example“I feel well.”
  • Good example“I am well.”
  • Good example“I am not well; please take me to the hospital.”

But if you’re describing your emotional state, use good.

  • Good example“I’m good! I aced my English final.”
  • Good example“I’m not so good. I failed calculus.”
  • Good example“We had a good time at the party.”

Still need help? Check out this quick lesson on good vs. well.

Grammar Rules You Should Learn #5: The Difference Between Their, They’re, and There

Peeve submitted by Natalie H.

“They’re over there, holding their bags”

When Natalie isn’t chasing down one of her many kids, she’s chasing down grammar errors at Kibin. She admits that one grammar rule she’s a stickler for is making sure people know the difference between their, they’re, and there.

grammar rules their they're there
Original photo by Emmey

I know you’ve probably heard this grammar rule more than a few times. Maybe you’ve even made an attempt to improve your understanding of it. But if it’s still causing you headaches, let’s see if we can sort it out!

I’ll start with the easy one. The word they’re is a contraction of the words they and are.

helpful hintHelpful Hint: If you can switch they’re with they are in your sentence, you know you have the right word.

Here are some examples of the proper usage of they’re:

  • Good example“They’re very funny.” (They are very funny.)
  • Good example“They’re living in a Malibu mansion because they’re filthy rich.” (They are living in a Malibu mansion because they are filthy rich.)
  • Good example“They’re hosting a big party Friday night.” (They are hosting a big party Friday night.)

Their, on the other hand, is used to indicate possession. For example, the words its, your, his, hers, and ours indicate possession (these are called possessive adjectives).

helpful hintHelpful Hint: If you can switch their with our and the sentence still sounds right, you know you are using the right word.

Here are some examples.

Good example“Their sense of humor makes me laugh.”

In this example, the sense of humor belongs to them, so use the possessive form. (Helpful hint test: Our sense of humor.)

Good example“Their mansion in Malibu is beautiful.”

Again, the mansion belongs to them, so we use possessive. (Helpful hint test: Our mansion in Malibu.)

Good example“Their party is going to be big!”

In this sentence, the party belongs to them, so we use possessive. (Helpful hint test: Our party.)

The third form, there, is used to indicate a location of an object or the existence of something.

helpful hintHelpful Hint: When you use there as a location indicator, you can easily swap in the word “here.” If it sounds right, you know you have the correct word. Unfortunately, this doesn’t work in sentences where there establishes the existence of something (i.e., let here be light!).

Here are some examples:

  • Good example“There is the road to Malibu.” (Helpful hint test: “Here is the road to Malibu.)
  • Good example“There she is!” (Helpful hint test: Here she is!)


  • Good example“There are a lot of people at the party.”

In this last example, our helpful hint test doesn’t really work. This is one of those existence-establishing uses, so “here are a lot of people at the party” doesn’t sound right. That said, it sounds better than “our are a lot of people,” so you know it’s not “their.” It also sounds better than “they are are a lot of people,” so you know it’s not “they’re.”

Need practice? Try this their/they’re/there quiz!

Grammar Rules You Should Learn #6:  Don’t Use Plural Pronouns with Singular Antecedents or Vice Versa

Peeve submitted by Crystal W.

“The hamster is adorable. I want it!”

Oh my! I know this one sounds complicated, doesn’t it?

First, let’s define a pronoun. A pronoun is simply a substitute for a noun. For example, using she instead of Molly or them instead of hot dogs. And plural, of course, means there is more than one. So it stands to reason that you would use a plural pronoun to talk about more than one thing. For example:

Good example“I love hot dogs, so I ate them all.”

In this example, hot dogs is the plural noun, and them is the plural pronoun. Easy right?

If you want to go crazy learning pronouns, I recommend checking out this detailed list of pronouns.

Now let’s define an antecedent (I swear grammarians invent these complicated words just to make language seem harder than it really is). An antecedent is simply the noun that the pronoun is replacing.

So again, in our sample sentence, “I love hot dogs, so I ate them all,” the word hot dogs is still a noun, but it’s also an antecedent (just like you can be both a sister and a friend).

Without the antecedent, you would have no idea what the word them refers to, as in this example, “I love them, I ate them all.”

If I said this to you, you’d have to ask me, “Wait, what did you eat? Better not be my Girl Scout cookies!”

grammar rules antecedents

So back to our rule. You need to have an agreement between your antecedent and your pronoun. If you have a plural antecedent (hot dogs), you also need to have a plural pronoun (them).

It just sounds silly and wrong to say:

Bad Example“I love hot dogs, so I ate all of it.”

Similarly, if you have a singular antecedent, you had better have a singular pronoun too. As in this example:

Good exampleThe student is in trouble. The principal is expelling her.”

Definitely don’t write:

Bad ExampleThe student is in trouble. The principal is expelling them.”

If you do, Crystal will have to correct you.

Check out this lesson to learn more about antecedents.

Grammar Rules You Should Learn #7: Learn the Difference Between If and Whether

Peeve submitted by Jared M.

Whether or not here I come… I’m going to find you if it’s the last thing I do!”

When Jared isn’t playing Frisbee golf in Argentina, he’s working up a storm editing at Kibin. He says it irks him when people mix up the words if and whether.

You’d think this one would be easy, wouldn’t you? But it turns out there is a lot of nuance in the difference between these two seemingly simple words.

As a general rule of thumb, you should use if in instances where your sentences are conditional.  For example:

Good example“We will cook a vegetarian meal if you come to dinner tonight.”

In this sentence, cooking a vegetarian meal is conditional because it will only happen if you come to dinner tonight.

You should use whether in instances when your sentence presents two alternatives. For example:

Good example“I have to decide whether to cook a vegetarian meal tonight.”

The two alternatives in this sentence are to either cook a vegetarian meal or not cook a vegetarian meal.

helpful hintHelpful Hint: Try restating the phrase using whether or not in place of the word if or whether. If it doesn’t change your intended meaning and it makes sense, use whether. For example:

Good example“I have to decide whether or not to cook a vegetarian meal tonight.”

This sentence makes perfect sense.

But what happens if we use whether in the other sentence?

Bad Example“We will cook a vegetarian meal whether or not you come to dinner tonight.”

That completely changes the meaning from our intended meaning (we will cook vegetarian only if you show up) to a new meaning (we will cook vegetarian regardless of whether you show up or not). So in this case, stick with if.

There’s a lot more to this rule than that, and if you’re interested in learning even more, I recommend this lesson on the difference between if and whether.


Phew! So there you have it, 7 grammar rules that you should really know! We covered a lot of ground, and hopefully you learned something new. If nothing else, you definitely learned that the Kibin editors are a picky bunch.

Let me know in the comments if there are any grammar rules that really offend you when they’re broken.  Or, perhaps, there is a grammar rule or two that has you downright confused.

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