Parts of a Sentence: Subject, Verb, Object

Every complete English sentence needs, at minimum, a subject (who or what performs the action) and a verb (the action or state). Many sentences add an object (who or what receives the action). The basic English word order is Subject-Verb-Object (SVO).

Worked example: "The lecturer (subject) explained (verb) the assignment (object)." Reordering these elements without proper grammatical signals produces confusion, which is why English relies heavily on strict word order rather than word endings to show meaning.

Types of Sentences by Structure

• Simple sentence: one independent clause. "The students submitted their essays."
• Compound sentence: two independent clauses joined by a coordinating conjunction (for, and, nor, but, or, yet, so) or a semicolon. "The students submitted their essays, and the lecturer began grading."
• Complex sentence: an independent clause plus at least one dependent clause. "Although the deadline was tight, the students submitted their essays."
• Compound-complex sentence: at least two independent clauses plus one dependent clause. "Although the deadline was tight, the students submitted their essays, and the lecturer began grading immediately."

Subject-Verb Agreement

A singular subject takes a singular verb; a plural subject takes a plural verb. Errors often arise when other words come between the subject and the verb.

Worked example (correct): "The list of items is on the table." (The true subject is "list," singular, not "items," so the verb agrees with "list," giving "is," not "are.") Incorrect: "The list of items are on the table."

Tense Consistency

A single passage or sentence should not shift tense without reason. Mixing past and present tense inconsistently is a common error in student writing.

Worked example (inconsistent): "She walked into the room and sees her friend." Corrected: "She walked into the room and saw her friend." (Both verbs kept in past tense.)

Common Clause Errors: Fragments and Run-ons

A sentence fragment is an incomplete thought punctuated as a full sentence, often missing a subject or verb, or being a dependent clause standing alone: "Because the exam was postponed." (incomplete — needs a main clause). A run-on sentence improperly joins two independent clauses with no punctuation or conjunction: "The exam was postponed the students were relieved." Correct it with a period, a semicolon, or a comma plus a conjunction: "The exam was postponed; the students were relieved."

Why This Matters for Your Exams

GST122 tests sentence structure directly through error-identification and sentence-correction questions, so the skill being assessed is recognizing which structural rule (agreement, tense, fragment, run-on) a given sentence violates and how to fix it economically — not rewriting the sentence from scratch.