Register is the level of formality a speaker or writer uses depending on the context, audience, and purpose. English has a wide register spectrum ranging from very informal (slang, casual conversation) to very formal (academic essays, legal documents, official correspondence). Understanding when and how to use formal language — as set out in the Cambridge Grammar guide to register — is essential for IELTS Writing, academic study, and professional life.
Key Features of Formal English
Formal English differs from informal English in vocabulary, grammar, sentence structure, and tone:
- No contractions: write do not, cannot, it is, they are (not don't, can't, it's, they're)
- Full forms of words: approximately not about; sufficient not enough; commence not start
- Passive voice: The study was conducted over six months rather than We did the study for six months
- Impersonal constructions: It is argued that … rather than I think …
- Longer, more complex sentences with subordinate clauses, relative clauses, and nominalisations
- No colloquialisms or slang: avoid a lot of, loads of, kids, stuff, basically, you know
Formal Vocabulary: Common Substitutions
Replacing informal words with formal equivalents immediately elevates your register:
- get / get better → obtain / improve / recover
- show → demonstrate / indicate / reveal
- look into → examine / investigate / analyse
- a lot of / lots of → a significant number of / a considerable proportion of
- think about → consider / reflect on / contemplate
- use → utilise / employ / apply
- find out → ascertain / establish / determine
Nominalisation
Nominalisation is the process of converting verbs and adjectives into nouns. It is a key feature of academic and formal writing: instead of The economy grew rapidly, write There was rapid growth in the economy. Nominalisations create a more impersonal, abstract style. Common examples: discuss → discussion; fail → failure; effective → effectiveness; apply → application.
Formal Sentence Structures
Formal writing uses more complex sentence patterns:
- Relative clauses: The study, which was conducted in 2024, found that …
- Participle clauses: Having considered all the evidence, the committee concluded that …
- Fronted adverbials: Despite considerable opposition, the policy was implemented.
- Impersonal passive: It has been suggested that … / It is widely accepted that …
Practice Exercises
Practise identifying and producing formal language in academic and professional contexts.
Grammar Quiz
Multiple-choice questions on identifying formal and informal register.
Cloze Dropdown
Choose the formal alternative to complete academic sentences correctly.
Complete the Sentence
Rewrite informal sentences in a formal register for academic writing.
True or False
Decide whether sentences use an appropriate formal register.
Practice What You've Learned
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Frequently Asked Questions
What is register in English and why does it matter?
Register is the level of formality a speaker or writer chooses depending on the situation, audience, and purpose. English has a wide spectrum from very informal (slang, casual chat) to very formal (legal documents, academic papers). Using the wrong register signals a lack of social or communicative competence: writing an email to a professor in casual language, or responding to a friend in stiff legalese. In IELTS Writing, register is directly assessed: Task 1 formal letter tasks require formal language; Task 2 essays require semi-formal to formal academic style.
What are the main differences between formal and informal English?
Key differences: (1) Contractions — informal uses them (can't, it's, they're); formal avoids them (cannot, it is, they are); (2) Vocabulary — informal uses common words (get, a lot, show); formal uses Latinate alternatives (obtain, considerable, demonstrate); (3) Sentence complexity — formal uses longer, more complex sentences with relative and participle clauses; informal uses shorter, simpler sentences; (4) Passive — formal writing uses the passive and impersonal constructions frequently; (5) Colloquialisms and slang are appropriate only in informal contexts.
What is nominalisation and how does it create a formal style?
Nominalisation converts verbs and adjectives into nouns: argue → argument; effective → effectiveness; the economy grew → economic growth. Nominalised sentences are often more concise, abstract, and impersonal — all hallmarks of formal academic writing. Example: The government decided to increase taxes (verb-centred, informal) vs The government's decision to increase taxation (nominalised, formal). Nominalisation also allows the writer to discuss processes and concepts as abstract entities, which is typical of academic and professional discourse.
Should I avoid using "I" in academic writing?
Traditional academic style discourages the first person (I, we) in favour of impersonal constructions: It is argued that... rather than I argue that.... However, modern academic style guidelines increasingly accept I in some contexts, particularly in humanities and social sciences, where the writer's perspective and positionality are relevant. In IELTS Writing, using I occasionally is fine, but avoiding it in favour of impersonal or passive constructions often raises the formal register. In Cambridge writing tasks, both approaches are accepted as long as the register is appropriate and consistent.
What are common informal words I should replace in academic writing?
Common substitutions: a lot of → a significant number of / a considerable amount of; get → obtain / receive / acquire; show → demonstrate / indicate / reveal; think → consider / believe / argue; look at → examine / analyse / investigate; start → commence / initiate / begin; kids → children; stuff → material / content / elements; really/very → highly / significantly / considerably; basically → fundamentally / essentially; ask → enquire / request; talk about → discuss / address / consider.
Is it always wrong to use informal language in writing?
No. Register depends on purpose, audience, and context. Informal language is entirely appropriate in personal emails, text messages, social media posts, personal narratives, and friendly letters. The problem arises when informal language appears in contexts that require formality: an academic essay full of colloquialisms, or a formal complaint letter using slang. The skill is matching your register to the context. In many professional contexts (start-ups, creative industries, social media), a semi-formal or even informal register is expected and valued.
How does formal language differ in speech versus writing?
Formal spoken English is less strict than formal written English. In academic presentations and formal meetings, speakers use full forms rather than contractions (cannot rather than can't), avoid slang, use more complex sentence structures, and employ discourse markers appropriate to speech (Furthermore, As I mentioned earlier, To summarise). However, spoken formal English allows more personal pronouns, hedging language, and occasional repetition for clarity. Written formal English has no real-time constraint, so it allows greater precision, complex sentence constructions, and denser information packaging.
What is "hedging" in formal academic writing?
Hedging is the use of cautious language to avoid making absolute claims that could be disproved. It is a fundamental feature of academic formality. Examples: This study suggests rather than This study proves; It appears that rather than It is clear that; The results may indicate rather than The results show. Hedging devices include modal verbs (might, could, may, would), adverbs (possibly, arguably, apparently), verbs (seem, appear, tend, suggest), and phrases (it is possible that, there is evidence to suggest, the data appears to indicate).
How does formal language affect IELTS Writing Task 1?
In IELTS Writing Task 1, the formal letter subtype (General Training) requires formal register throughout: Dear Sir/Madam, I am writing to..., I would be grateful if..., I look forward to hearing from you, Yours faithfully. The graph/chart/process description (Academic) requires semi-formal language that is objective and impersonal: The data illustrates..., It is evident that..., There was a significant increase of.... Contractions, slang, and personal opinions are inappropriate. Appropriate register contributes to the Task Achievement score in GT and the Task Response score in Academic.
What formal opening and closing phrases are used in business letters?
Formal British English letter conventions: Opening to unknown person: Dear Sir or Madam (closing: Yours faithfully). Opening to named person: Dear Mr Smith / Dear Dr Jones (closing: Yours sincerely). Formal openings: I am writing to enquire about / to complain about / to inform you that / with reference to. Formal closings: I would be grateful if you could..., I look forward to hearing from you, Please do not hesitate to contact me if you require any further information. Phrases to avoid: Hi there, Just wanted to say, Thanks, Talk soon — these are informal and inappropriate in formal business correspondence.