Punctuation in OET letters: commas, full stops, colons and apostrophes
In an OET Nursing letter, punctuation should make each sentence easy to read: end every complete sentence with a full stop, use commas after introductory phrases, around extra information and between items in a list, use apostrophes for possession ('the patient's wound'), and avoid joining two full sentences with only a comma. Bullet points and note-style dashes are best kept out of the letter body.
Why punctuation matters
Punctuation tells the reader where an idea ends and how ideas connect. In a nursing letter, a missing full stop or a misplaced comma can make a sentence ambiguous: does the medicine stop, or does the patient? Punctuation accuracy is part of the Language criterion, and clear sentence boundaries support Conciseness and Clarity.
This guide covers the punctuation that appears in almost every letter.
Full stops: one complete sentence, one full stop
The most common punctuation problem in OET-style letters is the comma splice: two complete sentences joined only by a comma.
| Error | Three ways to correct it |
|---|---|
| "She was discharged today, she will see her GP next week." | "She was discharged today. She will see her GP next week." |
| "She was discharged today; she will see her GP next week." | |
| "She was discharged today, and she will see her GP next week." |
The opposite problem is a sentence fragment: a group of words with a full stop but no complete verb.
| Fragment | Complete sentence |
|---|---|
| "Admitted on 2 June with chest pain." | "She was admitted on 2 June with chest pain." |
| "Lives alone." | "He lives alone." |
| "Which was treated with antibiotics." | "She developed an infection, which was treated with antibiotics." |
Fragments often come from copying the style of the case notes. See case notes to full sentences.
Commas: five uses you need
| Use | Example (invented) |
|---|---|
| After an introductory phrase | "On admission, her blood glucose was high." / "Since discharge, he has walked daily." |
| Around extra information | "Mrs Osei, who lives alone, ..." / "Her husband, a retired nurse, ..." |
| Between items in a list | "He takes metformin, ramipril and atorvastatin." |
| Before a linking word joining two sentences | "Her pain has improved, but she still needs help with dressing." |
| Around linking adverbs | "Her wound, however, has not yet healed." |
When not to use a comma:
- Between a subject and its verb: ~~"The patient's daughter, will visit daily."~~
- Before an identifying clause: ~~"The tablets, that were stopped, ..."~~ (see relative clauses).
- Before "that" in reported speech: ~~"She reports, that she feels better."~~
Apostrophes
| Meaning | Correct | Common error |
|---|---|---|
| Belonging to one patient | "the patient's mobility" | "the patients mobility" |
| Belonging to a name ending in s | "Mr Davis's wife" or "Mr Davis' wife" | "Mr Davis wife" |
| Plural, no possession | "two dressings", "the 1990s" | "two dressing's" |
| "It" possessive | "the wound and its edges" | "it's edges" ("it's" = it is) |
Contractions such as "she's", "can't" and "doesn't" are informal. Write them in full in a formal letter: "she is", "cannot", "does not". See formal tone, genre and style.
Colons and semicolons
A colon introduces a list or an explanation after a complete sentence:
She has been prescribed two new medicines: furosemide and spironolactone.
Do not use a colon after a verb or preposition: ~~"She takes: aspirin and metformin."~~
A semicolon joins two closely related complete sentences, or separates list items that already contain commas. You do not need semicolons to write a good letter; a full stop is always safe.
Punctuation in the letter layout
| Part | Typical punctuation |
|---|---|
| Date | "1 November 2026" (no punctuation needed) |
| Re line | "Re: Mrs Grace Owusu, aged 74" |
| Salutation | "Dear Ms Patel," or "Dear Ms Patel" — be consistent |
| Titles | "Mr", "Mrs", "Dr" with or without a full stop; be consistent |
| Sign-off | "Yours sincerely," or "Yours faithfully," then name and title |
For the layout itself, see letter format, re line and salutation.
Worked example (invented case)
Weak paragraph:
Mr Haddad was admitted on 12 April, he had a fall at home. He has a wound on his left shin which, was dressed daily. His wound is healing, however it needs daily dressings. Lives with his son who works full time. The sons phone number is below.
Corrected paragraph:
Mr Haddad was admitted on 12 April after a fall at home. He has a wound on his left shin, which has been dressed daily. The wound is healing; however, it still needs daily dressings. He lives with his son, who works full time. His son's telephone number is given below.
Corrections: the comma splice became one sentence; the misplaced comma before "was" moved before "which"; "however" between two sentences takes a semicolon and comma; the fragment gained a subject; the possessive apostrophe was added.
Final punctuation check (one minute)
- Does every sentence have a subject, a verb and a full stop?
- Did you join any two sentences with only a comma?
- Are named-person clauses ("Mrs X, who...,") inside two commas?
- Is every "patient's / son's / GP's" apostrophe in place, and every "it's" really "it is"?
- Are contractions written in full?
- Are the salutation and sign-off punctuated the same way?
Practise and check
Practise a timed letter at /writing/, or check a letter you have written to see grammar and punctuation corrections marked on your own text. medEmu covers OET Writing for Nursing only; its grades are estimates, and it is not affiliated with OET.
Related: common OET Writing mistakes and articles a/an/the.
Sources
This guide is medEmu's writing advice, not official OET guidance; all patients and details are invented for practice. The network used for this run could not reach oet.com, so no OET test facts are stated beyond the criterion names. For OET's official Writing information, see oet.com.