🧵 Grammar · Clauses, Connectors & Sentence Style
Formal vs Informal Grammar (Register)
One idea, two grammars — learn how contractions, phrasal verbs and passive voice shift with how formal the situation is.
Grammar › Clauses, Connectors & Sentence Style › Formal vs Informal Grammar (Register)
The rule in one sentenceFormal English favours full verb forms, single-word verbs and the passive voice; informal English favours contractions, phrasal verbs and the active voice — the grammar itself signals how formal a sentence is, not just the words you pick.
What is “register” — and why is it grammar, not just vocabulary?
Register is how formal or informal your English is for the situation you’re in. Most learners think register is only about word choice — swap “kids” for “children” and you’re done. But English actually changes its grammar between formal and informal contexts: which verb forms you contract, whether you use phrasal verbs or single-word verbs, and whether you build sentences in the active or passive voice.
Think about the gap between a broadsheet newspaper’s review of The Science of Sleep and a friend’s text message about it. The newspaper writes in full sentences with no contractions and often the passive voice: “The Science of Sleep was praised for its inventive, handmade visual effects, and Rust and Bone was praised for its performances.” Your friend texts something closer to: “Have you seen The Science of Sleep yet? It’s so good, you have to watch it!” Same film, same facts — completely different grammar.
Informal grammar is built for speed and closeness: contractions save syllables, phrasal verbs feel conversational, and the active voice keeps a clear “who did what”. Formal grammar is built for distance and precision: full forms sound careful, single-word verbs sound exact, and the passive voice lets a writer foreground the film, the result or the event rather than the person behind it.
🎬 Compare: “The critics didn’t like Cocaine Bear.” (informal — a chat with a friend) vs. “The critics did not favourably review Cocaine Bear.” (formal — a film studies essay).
Same opinion, same film — but the second version reads like it belongs in an essay, purely because of the grammar.
Neither register is “better” English — they’re tools for different jobs. Writing a cover letter for a job at a production studio needs formal grammar; texting a friend about the new Marvel film doesn’t. The skill is choosing correctly, and switching cleanly, rather than mixing the two by accident.
How to build it
Contractions
Informal English keeps contractions; formal English always spells both words out in full.
Informal: “The critics didn’t like Morbius.”
Formal: “The critics did not like Morbius.”
Phrasal verbs → single-word verbs
Formal writing swaps everyday phrasal verbs for a single Latinate word with the same meaning.
Informal: “Tenants look into strange disappearances in Delicatessen.”
Formal: “Tenants investigate strange disappearances in Delicatessen.”
Passive voice in formal writing
Informal (active): “Audiences praised A Very Long Engagement and gave it strong reviews.”
Formal (passive): “A Very Long Engagement was praised by audiences and was given strong reviews.”
Vocabulary register shifts
Informal: “This flick is awesome — my kids loved it!” (about La Femme Nikita)
Formal: “This film is excellent and appeals to children of all ages.” (about La Femme Nikita)
When to use which
Informal register
- Texting a friend: “OMG have you seen Booksmart yet? It’s amazing!”
- Fan forums and social media: casual posts ranking every Bridget Jones film.
- Everyday conversation: recapping the twist in Lucy (2014) over dinner.
- Natural film dialogue: characters in Step Brothers speak informally because that’s how real people talk.
Formal register
- Academic essays: analysing the cinematography of a film by Jean Cocteau.
- Official studio press releases: announcing the release date of Despicable Me 4.
- Broadsheet newspaper reviews: of a film directed by Mathieu Kassovitz.
- Professional emails or cover letters: referencing your work on the crew of A Prophet.
Signal words
These connectors and fillers are strong clues to which register a sentence belongs to.
Formal connectors
Informal connectors & fillers
Visual guide
Teacher Teddy’s illustrated guide to this rule is being drawn — the full swipe-through infographic will appear here soon.
Common mistakes
❌ Madame Web wasn’t accepted well by critics. (in a film studies essay)
✅ Madame Web was not well received by critics.
Formal writing avoids contractions completely — spell both words out.
❌ Jacques Tati looked into visual comedy techniques for his films, much like the fantasy sets of Beauty and the Beast (1946). (in an academic essay)
✅ Jacques Tati investigated visual comedy techniques for his films, much like the fantasy sets of Beauty and the Beast (1946).
Formal essays generally prefer a single-word Latinate verb over a phrasal verb.
❌ The new Orpheus trailer was watched by me three times last night. (in a text to a friend)
✅ I watched the new Orpheus trailer three times last night.
Informal speech favours the active voice with a clear “I” — heavy passive sounds stiff in conversation.
❌ Critics couldn’t agree on Megalopolis, however they praised the acting. (in a formal review)
✅ Critics could not agree on Megalopolis; however, they praised the acting.
Don’t mix an informal contraction with a formal connector like “however” in the same sentence — pick one register and stay in it.
Exceptions & tricky cases
Four cases where the formal/informal line blurs — knowing these separates B1 from C1.
1. Some phrasal verbs have no formal replacement. “Fall apart” has no neat single-word substitute, so it survives even in formal writing.
✅ “The plot of Argylle falls apart in the third act,” writes the critic, in an otherwise formal review.
2. Film dialogue stays informal regardless of the film’s genre. Even a serious historical drama like Lincoln contains contractions in its dialogue, because characters need to sound like real people speaking.
✅ “I don’t think we’re ready,” a character says in Lincoln — informal grammar, formal subject matter.
3. The passive can drop the agent entirely. When the “doer” is obvious or unimportant, formal writing often omits “by…” altogether.
✅ “Diabolique was praised for its shocking twist ending.” (no need to name every critic — it’s understood.)
4. Film journalism sits in the middle. A magazine review of a Luc Besson film might use full grammatical sentences (formal) but relaxed, punchy vocabulary (informal) — register is a spectrum, not a strict on/off switch.
✅ “Luc Besson is not simply an action director — his visual style, much like Michel Gondry’s, is genuinely distinctive,” reads a typical review, mixing formal structure with lively word choice.
Practice: choose the right register
Eight quick questions. Pick the answer that matches the register the sentence needs.
1. Which fits a film studies essay about Darkest Hour?
Formal writing spells contractions out in full.
2. In Mood Indigo, the two leads ___ a strange, dreamlike illness together.
“Investigated” is the formal single-word equivalent of the phrasal verb “looked into”.
3. Texting a friend: “Have you seen Monsieur Hulot’s Holiday yet? It’s ___!”
“Awesome” is the informal choice — fine for a text between friends.
4. A broadsheet review of Gothika: “The film ___ mixed reviews on release in 2003.”
The passive “was given” puts the focus on the film, which suits formal review writing.
5. Which is correct, fully formal English about The Wages of Fear?
The first sentence stays consistently formal: no contraction, and “however” is correctly punctuated with a semicolon and comma.
6. Jacques Audiard ___ extensive research before filming one of his character-driven crime dramas.
“Conducted” is the formal single-word verb; “did loads of” is casual, spoken English.
7. A fan forum post about Dheepan: “The ending totally ___ me!”
A casual forum favours the everyday phrasal verb “caught out” over the more formal “deceived”.
8. Studio press release: “City of Lost Children ___ several times during pre-production.”
Formal, official writing prefers the single-word Latinate verb “postponed” over the phrasal “put off”.
Keep going
📬 New grammar lessons land every week — subscribe to the newsletter at the bottom of this page so you never miss one ↘