Find the sentence’s core
A sentence normally contains a subject and a predicate. The subject identifies who or what the sentence is about; the predicate says something about that subject and includes a verb. In “The curious student opened the book,” the simple subject is student and the main verb is opened. An independent clause can stand alone as a complete sentence. A dependent clause cannot stand alone in standard formal writing: “because the rain stopped” leaves the reader waiting to learn what happened. An imperative such as “Read carefully” has an understood subject, you.
Make subjects and verbs agree
In standard written English, a present-tense verb must agree with its subject. “The student reads” uses a singular subject; “The students read” uses a plural one. Words between the subject and verb can distract you. In “The box of pencils is open,” box is the subject, so is is appropriate even though pencils is plural. A compound subject joined by and is usually plural: “Maya and Leo study.” Different English varieties have their own systematic grammar; this lesson practices conventions commonly expected in formal edited English.
Use punctuation to show relationships
A comma alone usually cannot join two independent clauses in formal writing. “I studied, I felt ready” is a comma splice. You can write “I studied, and I felt ready,” “I studied; I felt ready,” or two separate sentences. Apostrophes have different jobs. In a contraction, they mark omitted letters: “it is” becomes “it’s.” For a singular possessive noun, add ’s: “the student’s notebook.” For a regular plural already ending in s, add the apostrophe after the s: “the students’ notebooks.” A normal plural such as books needs no apostrophe.
Choose words by their function
Its is possessive, while it’s means “it is” or “it has.” Their indicates possession, there can refer to a place, and they’re means “they are.” A practical check is to expand the contraction: if “they are” fits, they’re may be the intended word. Adjectives typically modify nouns; adverbs can modify verbs, adjectives, or other adverbs. In “She spoke quietly,” quietly describes how she spoke. Not every adverb ends in -ly, and a word’s function depends on its sentence. Proofread for meaning first, then check individual forms in context.
Further reading
These resources offer a fuller treatment of the underlying concepts. The lesson, quiz wording, and flashcards here were created for this project.
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