There are several ways of apologizing and accepting apologies. You apologize when you have upset someone or caused trouble for them in some way.

The commonest way of apologizing is to say 'Sorry' or 'I'm sorry'. When using 'I'm sorry', you can use adverbs such as 'very', 'so', 'terribly', and 'extremely' to be more emphatic.

'Stop that, please. You're giving me a headache.' – 'Sorry.'

Sorry I'm late.

I'm sorry about this morning.

I'm sorry if I've distressed you by asking all this.

I'm very sorry, but these are vital.

I'm terribly sorry – we shouldn't have left.

When apologizing for accidentally doing something, for example stepping on someone's foot, some people say 'I beg your pardon' instead of 'Sorry'. This is rather old-fashioned.

She bumped into someone behind her. 'I beg your pardon,' she said.

Speakers of American English usually say 'Excuse me' in the above situations.

You use 'Excuse me' to apologize politely to someone when you are disturbing or interrupting them, or when you want to get past them. This is also the expression to use when you want to speak to a stranger.

Excuse me for disturbing you at home.

Excuse me butting in.

Excuse me, but is there a fairly cheap restaurant near here?

Excuse me, do you mind if I move your bag slightly?

The expression 'Pardon me' is used by some speakers of American English.

Pardon me, Sergeant, I wonder if you'd do me a favour?

When you are disturbing or interrupting someone, you can also say 'I'm sorry to disturb you' or 'I'm sorry to interrupt'.

I'm sorry to disturb you again but we need some more details.

Sorry to interrupt, but I've some forms to fill in.

You also say 'Excuse me' when you have to leave someone for a short time in order to do something.

Excuse me. I have to make a telephone call.

Will you excuse me a second?

You can use 'Excuse me' or 'I beg your pardon' to apologize when you have done something slightly embarrassing or impolite, such as burping, hiccupping, or sneezing.

You say 'I beg your pardon' to apologize for making a mistake in what you are saying, or for using the wrong word. You can also say 'sorry'.

It is treated in a sentence as a noun – I beg your pardon – as an adjective.

It's in the southeast, sorry, southwest corner of the USA.

When you want to apologize in a formal way, you can say explicitly 'I apologize'.

I apologize for my late arrival.

How silly of me. I do apologize.

I really must apologize for bothering you with this.

Another formal expression, used especially in writing, is 'Please accept my apologies'.

Please accept my apologies for this unfortunate incident.

You can use forgive in polite expressions like 'Forgive me' and 'Forgive my ignorance' to reduce the directness of what you are saying, and to apologize in a mild way for saying something that might seem rude or silly.

Look, forgive me, but I thought we were going to talk about my book.

Forgive my ignorance, but who is Jennifer Lopez?

Regret is often used in public notices and formal announcements.

London Transport regrets any inconvenience caused by these repairs.

The notice said: 'Dr. Beamish has a cold and regrets he cannot meet his classes today.'

To accept an apology, you normally use a short fixed expression such as 'That's okay', 'That's all right', 'Forget it', 'Don't worry about it', or 'It doesn't matter'.

'I'm sorry about this, sir.' – 'That's all right. Don't let it happen again.'

'I apologize for my outburst just now.' – 'Forget it.'

She spilt his drink and said 'I'm sorry.' 'Don't worry about it,' he said, 'no harm done.'

'I'm sorry to ring at this late hour.' – 'I'm still up. It doesn't matter.'

Some words and expressions that are used to apologize are also used to ask someone to repeat something that they just said.