Grammar Essentials

Grammar is the scaffolding under your sentences. Most of the time the reader never notices it. When it breaks, that's all they notice.

Why Grammar Matters

Grammar is the structure that holds language together. Good grammar:

• Makes your meaning clear
• Makes you appear credible
• Prevents misunderstandings
• Shows respect for readers

Remember: Grammar serves clarity, not perfection. The goal is effective communication.

Subject-Verb Agreement

Basic Rule

Subjects and verbs must match in number (singular/plural).

Correct:

• The dog barks. (singular)
• The dogs bark. (plural)
• She writes. (singular)
• They write. (plural)

Common mistakes:

Tricky Cases

1. Phrases Between Subject and Verb

Ignore words between subject and verb.

Pattern: Subject + [prepositional phrase] + Verb

Correct:

• The box of chocolates is on the table.
• The keys to the car are missing.
• One of the students has finished.

Tip: Cover the middle phrase to check: "The box is" / "The keys are"

2. Compound Subjects

With "and": Use plural verb

• John and Mary are coming.

With "or" or "nor": Verb agrees with nearest subject

• Neither John nor Mary is coming.
• Neither the teacher nor the students are coming.

3. Indefinite Pronouns

Always singular: each, every, either, neither, one, someone, anyone, everyone, no one

• Everyone is here.
• Each of the books has a cover.

Always plural: both, few, many, several

• Both are correct.
• Many were present.

Depends on context: some, all, most, none

• Some of the pie is gone. (pie = singular)
• Some of the pies are gone. (pies = plural)

Verb Tenses

The Main Tenses

Common Tense Mistakes

1. Tense Shifting

Wrong: I walked to the store and buy bread. Right: I walked to the store and bought bread.

Wrong: She says she will come, but she never showed up. Right: She said she would come, but she never showed up.

2. Present Perfect vs. Past Simple

Present Perfect: Connection to now

• I have lived here for five years. (still living here)

Past Simple: Finished in the past

• I lived there for five years. (not living there anymore)

3. Using "Would" for Habitual Past

Correct: When I was young, I would play outside every day. Correct: When I was young, I played outside every day.

Wrong: When I was young, I would be happy. (not habitual) Right: When I was young, I was happy.

Pronouns

Pronoun-Antecedent Agreement

Pronouns must match their antecedents in number and gender.

Wrong: Each student must bring their book. Right: Each student must bring his or her book. Better: Students must bring their books. (make plural)

Wrong: The company announced their new policy. Right: The company announced its new policy.

Pronoun Case

Common mistakes:

Tip: Remove the other person to check.

• "Between you and I" → "Between I" ✗
• "Between you and me" → "Between me" ✓

Pronoun Reference

Pronouns must clearly refer to a specific noun.

Unclear: John told Mark that he was wrong.

• Who was wrong? John or Mark?

Clear: John admitted he was wrong when talking to Mark.

Unclear: I removed the books from the boxes and threw them away.

• What was thrown away? Books or boxes?

Clear: I removed the books from the boxes and threw the boxes away.

Modifiers

Misplaced Modifiers

Place modifiers near the words they modify.

Wrong: I nearly ate all the cookies.

• Suggests you almost ate but didn't.

Right: I ate nearly all the cookies.

• You ate most of them.

Wrong: She served coffee to the guests in paper cups.

• Were the guests in paper cups?

Right: She served coffee in paper cups to the guests.

Dangling Modifiers

Make sure modifiers have something to modify.

Wrong: Walking down the street, the trees were beautiful.

• Trees can't walk.

Right: Walking down the street, I saw beautiful trees.

Wrong: To improve writing, practice is necessary. Right: To improve writing, you must practice.

Comma Usage

When to Use Commas

1. Compound Sentences

Before coordinating conjunctions (and, but, or, nor, for, so, yet) joining independent clauses.

Correct: I wrote the draft, and she edited it.

No comma: I wrote the draft and edited it. (one subject)

2. After Introductory Elements

After introductory words, phrases, or clauses.

Correct:

• However, I disagree.
• In the morning, I write better.
• After finishing the draft, I took a break.

3. Lists (Serial Comma)

Between three or more items.

Correct: I need paper, pens, and pencils.

Note: The comma before "and" (Oxford comma) is optional but recommended for clarity.

Without Oxford comma:

I'd like to thank my parents, Oprah and God.

• Suggests parents are Oprah and God

With Oxford comma:

I'd like to thank my parents, Oprah, and God.

• Four separate entities

4. Non-Essential Information

Around information that can be removed.

Correct: My brother, who lives in Boston, is visiting.

• I have one brother; his location is extra info.

No commas: My brother who lives in Boston is visiting.

• I have multiple brothers; specifying which one.

5. Direct Address

When addressing someone directly.

Correct: Thanks, John, for your help.

Meaning changes without commas:

• "Let's eat, Grandma!" (addressing Grandma)
• "Let's eat Grandma!" (cannibalism)

When NOT to Use Commas

Don't separate subject and verb:

• Wrong: The book I read yesterday, was excellent.
• Right: The book I read yesterday was excellent.

Don't separate verb and object:

• Wrong: She quickly wrote, the report.
• Right: She quickly wrote the report.

Apostrophes

Possessives

Singular Nouns

Add 's

Correct:

• the dog's bone
• James's book (or James' book, both acceptable)
• the boss's office

Plural Nouns Ending in S

Add only '

Correct:

• the dogs' bones
• the students' books
• the teachers' lounge

Plural Nouns Not Ending in S

Add 's

Correct:

• the children's toys
• the women's rights
• the people's choice

Contractions

Apostrophes show missing letters.

Common Apostrophe Errors

Key distinction:

• it's = it is
• its = belonging to it

Commonly Confused Words

Homophones (Sound Alike)

Other Common Confusions

Sentence Fragments

What Is a Fragment?

An incomplete sentence missing subject, verb, or complete thought.

Fragments:

• Because I was tired.
• Running down the street.
• A beautiful day.

Complete sentences:

• I left early because I was tired.
• I saw him running down the street.
• It was a beautiful day.

When Fragments Are Acceptable

In informal writing for emphasis or style:

• Question? Answer.
• Can't find words? Try these strategies.
• Absolutely not.

Run-on Sentences

Two Types

1. Fused Sentence

Two sentences joined with no punctuation.

Wrong: I love writing it helps me think.

Fixes:

• Period: I love writing. It helps me think.
• Semicolon: I love writing; it helps me think.
• Comma + conjunction: I love writing, and it helps me think.

2. Comma Splice

Two sentences joined with only a comma.

Wrong: I love writing, it helps me think.

Same fixes as above.

Parallel Structure

Keep similar elements in the same grammatical form.

Wrong: I like writing, to read, and running. Right: I like writing, reading, and running.

Wrong: She is smart, funny, and has talent. Right: She is smart, funny, and talented.

Wrong: The job requires attention to detail, working independently, and you must meet deadlines. Right: The job requires attention to detail, independent work, and meeting deadlines.

Active vs. Passive Voice

Active Voice (Preferred)

Subject performs action.

Structure: [Subject] [verb] [object] Example: The dog chased the cat.

Passive Voice

Subject receives action.

Structure: [Subject] [be verb] [past participle] (by [agent]) Example: The cat was chased by the dog.

When to Use Passive

1. Unknown actor: The window was broken.
2. Unimportant actor: Mistakes were made.
3. Focus on receiver: The president was elected.

Grammar-Checking Tools

Online Tools

• Grammarly: general checking
• Hemingway Editor: readability and simplicity
• ProWritingAid: style and grammar
• LanguageTool: open-source checker

Built-in Tools

• Microsoft Word: grammar and spell check
• Google Docs: basic grammar checking

Remember: Tools help but aren't perfect. Learn the rules yourself.

Practice Exercises

Exercise 1: Subject-Verb Agreement

Choose the correct verb:

1. The collection of books (is/are) impressive.
2. Either the teacher or the students (has/have) the key.
3. Everyone (need/needs) help sometimes.

Answers: 1. is, 2. have, 3. needs

Exercise 2: Fix Comma Errors

Add or remove commas:

1. After eating the dog went outside.
2. I need milk eggs and bread.
3. My friend who lives nearby is visiting.

Answers:

1. After eating, the dog went outside.
2. I need milk, eggs, and bread.
3. No change (if specifying which friend) OR My friend, who lives nearby, is visiting. (if I have one friend)

Exercise 3: Fix Pronoun Errors

Correct the pronouns:

1. Between you and I, this is difficult.
2. Each student must bring their book.
3. Me and John went to the store.

Answers:

1. Between you and me
2. Each student must bring his or her book (or make plural: Students must bring their books)
3. John and I went to the store

Summary

Essential grammar rules:

• Subject-verb agreement (singular with singular, plural with plural)
• Consistent verb tenses (don't shift unnecessarily)
• Correct pronoun case (I vs. me, she vs. her)
• Proper comma usage (compound sentences, introductory elements, lists)
• Apostrophes for possession and contractions
• Avoid fragments and run-ons
• Use parallel structure

Remember:

• Grammar serves clarity
• Learn rules, but tools help too
• Some rules are flexible in informal writing
• When in doubt, rewrite the sentence

Next Steps

Continue to 06-style-tone.md to develop your voice and match your tone to your audience.