Grammar / usage: Punctuation in formal writing
Subtopic: Section D · Grammar
How to structure your answer
Rule: punctuation marks the structure of a sentence and the relations between its parts. In formal writing, the central marks are the comma (lists, parenthetical remarks, separating subordinate from main clauses), the semicolon (joining two independent clauses without a conjunction, or separating list items that themselves contain commas), the colon (introducing a list, explanation or quotation), and the apostrophe (possession and contraction). The dash and the parenthesis offer parenthetical asides; the question mark is reserved for direct questions, never indirect ones.
Approach: for each clause, ask whether it is independent or subordinate; that decides whether a comma, semicolon or full stop is appropriate. For lists, use the serial (Oxford) comma when needed to remove ambiguity. For possessives, place the apostrophe before the 's' for singular owners, after the 's' for regular plural owners.
What an examiner expects: the rule stated cleanly; corrected sentences with the punctuation change underlined; a one-line justification.
Common pitfalls: (1) the comma splice — joining two independent clauses with a comma alone; (2) confusing 'its' (possessive) with 'it's' (it is); (3) putting a question mark after an indirect question ('She asked whether he was coming?'); (4) misusing the semicolon as a colon.
Detailed model answer
122 words · target 100 words · 8 min
Rule: Formal punctuation clarifies structure — commas separate items, semicolons join related independent clauses, colons introduce a list or explanation, dashes mark a strong break, apostrophes mark possession or contraction.
Worked examples: 'The report is long; however, it is well argued' (semicolon before conjunctive adverb). 'There are three goals: speed, accuracy and clarity' (colon introducing list). 'The Minister's statement was clear' (apostrophe for possession).
Quick check:
- She said she would come however she did not. She said she would come; however, she did not.
- The schools children performed well. The school's children
- My three priorities are reading writing and listening. My three priorities are reading, writing and listening.
- Its raining. It's raining.
- He arrived at 9 a m sharp. He arrived at 9 a.m. sharp.
What an examiner expects to see
- Comma: separates list items, sets off parenthetical remarks, follows introductory subordinate clauses.
- Semicolon: joins two independent clauses without a conjunction; separates list items that contain commas.
- Colon: introduces a list, explanation or quotation; never a substitute for a comma.
- Apostrophe: marks possession ('the minister's speech', 'the ministers' speeches') and contraction ('it's = it is').
- Dash and parenthesis: parenthetical asides; dash is more emphatic, parenthesis more discreet.
- Quotation marks: enclose direct speech and exact titles; punctuation usually inside the closing mark in BrE for full sentences quoted, outside for fragments.
- Question mark only for direct questions — never after indirect questions.
- Avoid the comma splice; use a semicolon, a full stop, or a conjunction.
- Use the serial (Oxford) comma to avoid ambiguity in lists.
- Practice sentences for the examinee to repunctuate.
Concrete cases, schemes and judgments
- Wrong (comma splice): 'It was raining, we stayed indoors.' Right: 'It was raining; we stayed indoors.' OR 'It was raining, so we stayed indoors.'
- Wrong (apostrophe): 'The committee published it's report.' Right: 'The committee published its report.' ('Its' = possessive; 'it's' = it is.)
- Wrong (question mark): 'She asked whether the meeting was over?' Right: 'She asked whether the meeting was over.' (Indirect question — no question mark.)
- Wrong (semicolon as colon): 'There are three options; oral, written and practical.' Right: 'There are three options: oral, written and practical.' (Colon introduces the list.)