English distinguishes between formal and informal speech mainly through vocabulary, tone, and sometimes grammar. Choosing the right level of formality depends on your relationship with the listener and the setting.
Formal Speech
Formal speech uses polite expressions, complete sentences, and more precise vocabulary. It appears in business, academic, and official contexts where respect and professionalism matter. Speakers avoid slang and contractions in formal speech.
Please assist the client with their inquiry.
Informal Speech
Informal speech is relaxed and natural, featuring contractions, colloquialisms, and sometimes slang. It suits conversations with friends, family, and casual acquaintances. Shorter sentences and everyday expressions characterize informal speech.
Addressing People
English does not distinguish formal and informal you by different pronouns, but tone and titles signal respect. Using Mr., Ms., Dr., or job titles plus last name keeps speech formal, while first names or nicknames mark informality. Adding please and thank you also helps.
Polite Expressions
Formal speech favors polite formulae like "Could you please..." and "I would appreciate if...". Informal speech uses more direct requests such as "Can you..." or "Would you...". Turning requests into questions softens them in both registers.
Vocabulary
Some words have distinct formal and informal equivalents. Formal speech prefers words like assist, request, and purchase, while informal speech favors help, ask for, and buy. Choosing the right word shapes the tone of your message.
| Formal Word | Informal Word | |
|---|---|---|
| assist | help | |
| request | ask for | |
| purchase | buy | |
| commence | start | |
| require | need | |
| obtain | get |
Tone
Formal tone is courteous, measured, and impersonal, avoiding jokes and emotional language. Informal tone is friendly, warm, and expressive, often including humor and personal remarks. Matching tone to context builds rapport.
Summary
Use formal speech in professional and unfamiliar settings with polite expressions and precise vocabulary. Use informal speech with friends and in casual contexts for natural, relaxed communication. Pay attention to address, vocabulary, and tone to signal your level of formality.
Last updated: Fri Oct 24, 2025