What is the difference between formal and informal speech?

Formal writing is used for essays, reports and business letters. It has a more serious tone and is clear and direct.

Formal writing uses correct grammar and punctuation, a more complex sentence structure and specific vocabulary relating to the topic.

Gorillas, despite their large stature and remarkably sharp canine teeth, are strictly vegetarian.


Informal writing: diary, text message, writing to friends.

Informal writing is more casual as if we were speaking to a friend.

It uses more contractions and abbreviations (it’s instead of it is, I’d instead of I would). Slang, abbreviated language like LOL or ASAP, and clichés (e.g. raining cats and dogs) are also common.

Man, did you see those teeth on that gorilla? I bet he could shred ya to pieces.

When writing letters and emails we can use either a formal or informal style depending on who the letter is being addressed to.

For the next set of questions, you will be asked to state whether a sentence is formal or informal.


True or False. The sentence below is formal.

What is everyone looking at? I can't see nothing!

The answer is false. The sentence is informal and is grammatically incorrect.