Register & Tone — Formal vs. Informal Grammar
Matching your grammar to the situation: when to use contractions, phrasal verbs and casual language, and when to switch to a formal register.
Most CELPIP Writing Task 1 prompts call for a semi-formal register: polite and clear, with contractions allowed but no slang. This means one consistent level throughout — full forms or contractions, but never both, and no phrasal verbs like "set up" mixed with stiff Latinate ones like "formally lodge." Match your grammar to the reader named in the prompt.
- What's the difference between formal and informal grammar?
- Formal uses full forms (I would, do not) and Latinate verbs (request, assist) with no slang; informal uses contractions (I'd, don't) and phrasal verbs (set up, find out) with a friendly tone.
- When should I use formal vs. informal register?
- Use formal for complaints or writing to managers and officials; use informal for emails to friends or colleagues.
- What's the biggest register mistake to avoid?
- Mixing levels in one text — for example, writing "I am writing to formally request" and then "thanks, that'd be great!" — so pick one register and hold it from greeting to sign-off.
- 1.Formal: full forms (I would, do not), Latinate verbs (request, assist), no slang. Used for complaints, managers, officials.
- 2.Informal: contractions (I'd, don't), phrasal verbs (set up, find out), friendly tone. Used for emails to friends/colleagues.
- 3.CELPIP Task 1 emails are usually SEMI-formal: polite and clear, contractions acceptable but no slang.
- 4.Keep ONE register throughout — do not mix "I am writing to formally request" with "thanks, that'd be great!".
Register is the level of formality
The same idea can be said formally or informally — and the grammar changes with it:
| Informal | Formal | |
|---|---|---|
| forms | I'd like, don't, can't | I would like, do not, cannot |
| verbs | find out, put off, get | determine, postpone, receive |
| openers | Hi Sam, | Dear Mr. Smith, / Dear Sir or Madam, |
| closers | Cheers, / Thanks! | Sincerely, / Kind regards, |
Phrasal vs. single-word verbs
Phrasal verbs (set up, find out, put off) sound conversational; their single-word equivalents (establish, discover, postpone) sound formal. Match the verb to the reader.
Friend: "Let's set up a meeting." / Manager: "I would like to arrange a meeting."
Match the reader
- Writing to a company, landlord, or official → formal: full forms, polite framing, no slang.
- Writing to a friend or close colleague → informal: contractions and a warm tone are natural.
Stay consistent
The biggest register error is mixing levels in one text:
✗ "I am writing to formally lodge a complaint. Anyway, hope you can sort it out soon, thanks!"
Pick a level and hold it from greeting to sign-off.
CELPIP application
Writing Task 1 tells you who the reader is. Getting the register right — and keeping it consistent — is part of Task Fulfillment. Most prompts call for a polite, semi-formal tone: clear and courteous, neither stiff nor slangy.
Check yourself
A quick self-check on this lesson — pick an answer, then see the explanation. Not graded.
Grow your Grammar vocabulary
The right words lift your score. Study task-specific CELPIP word lists with definitions, examples and exam tips.
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