A ‣ Formal English 
Formal English is more common in writing, but you will also hear examples in more formal spoken English, e.g. announcements, speeches, television news, or discussions.
NOTICE IN A CAFE: Only food purchased [bought] here may be eaten on the premises [here].
BUSINESS LETTER: I regret to inform you [I am sorry to say] that we are unable to …
INFORMATION NOTICE: If you require [need] further assistance [more help], please contact the above address.
FORMAL LETTER: We are not in a position to grant [give or allow] you a visa to this country.
POLICE STATEMENT: The man is being questioned regarding [about] the robbery last night.
THEATRE ANNOUNCEMENT: The play will commence [start] in two minutes.
STATION ANNOUNCEMENT: The next train to depart [leave] from platform 7 will be the 7:22 to Reading.
AIRPORT ANNOUNCEMENT: Will passengers for Miami please proceed to [go to] gate 36.
B ‣ Informal English 
Informal language is more common in spoken English, and also in most emails or letters to friends. The words and phrases in bold in these dialogues are all informal.
A: Who’s Callum?
B: A mate [a friend] of mine.
A: Really?
B: Yeah, I see him quite a bit [often]; he’s a nice bloke [man].
A: Toby, I’m afraid I can’t make it [come] this evening.
B: Oh, that’s a shame.
A: Yeah, I’m sorry, but the thing is [the problem is], Ella’s not well, so I’ll have to look after the kids [children].
B: OK, don’t worry. There will still be twelve or so [about twelve] at the meeting, and I’ll ring you later and let you know what happens.
A: Cheers [thanks]. That would be great.
A: I bet [I’m sure] you’re hungry.
B: Yes, I’m dying for something to eat. [want to eat something very much]
A: Well, I think you’ll find some stuff in the fridge.
A: What are you up to this evening? [What are you doing?]
B: Nothing much. Why?
A: Well, would you like to see the new Coen Brothers film? I’ve heard it’s great [very good; syn terrific].
B: Really? My brother saw it and said it was a load of rubbish [terrible].
Language help
We often use the uncountable noun stuff, especially in spoken English, to refer to an uncountable noun or a group of things. We do this when others know what we are talking about, or if we don’t need to be exact.
Put this stuff in the cupboard. [e.g. plates, food, toys]
We carried our camping stuff [equipment].
What’s this stuff in the fridge in the blue bottle? [liquid]