Grammar Rules

40 full pillar guides — the actual rule, common real-world mistakes, and genuine example sentences.

• Active vs. Passive Voice
• Apostrophes
• Articles: A, An, and The
• Capitalization Rules
• Collective Nouns
• Colons
• Comma Splices
• Commas
• Conditional Sentences
• Count vs. Non-Count Nouns
• Dangling Modifiers
• Double Negatives
• Ellipses
• Em Dash vs. En Dash
• Fewer vs. Less
• Gerunds and Infinitives
• Hyphens vs. Dashes
• Irregular Plurals: the Rules Behind Them
• Its vs. It's
• Lie vs. Lay
• Modal Verbs
• The Oxford Comma
• Parallel Structure
• Plural Possessives
• Ending a Sentence with a Preposition
• Pronoun-Antecedent Agreement
• Quotation Marks
• Reported (Indirect) Speech
• Run-On Sentences
• Semicolons
• Semicolons vs. Colons
• Sentence Fragments
• Split Infinitives
• Subject-Verb Agreement
• The Subjunctive Mood
• "If I Were" — the Subjunctive Were
• Tense Consistency
• That vs. Which
• Who vs. Whom
• Whom in Questions