Slang: "ain't" (lesson & exercise)

Lesson:

For the first lesson, I thought I'd say a few words about a topic my students ask me about a lot - the word 'ain't'.

It's not surprising that students are interested in it. They hear it in songs all the time, and perhaps they've seen a teacher or two shake their heads as if it were a dirty word or something.

Is 'ain't' a dirty word? No, it isn't. You can say it on television. Your mother will not slap you if you say it. But it is slang, which means you shouldn't use it in formal situations. Also I would advise you never to use it in writing, except maybe things like SMS messages. In fact, I would advise you never to use it - not because it's a bad word, but because it sounds unnatural when most English learners say it.

So what is it? Well, originally, hundreds of years ago, 'ain't' was simply the short form of 'am not'. Just as 'is not' can become 'isn't' and 'will not' shortens to 'won't', 'ain't' was used to shorten 'am not'. The problem came when people started use 'ain't' to shorten other things, such as 'is not'. So because it was bad grammar to shorten 'is not' to 'ain't', the teachers of good English grammar decided to completely banish 'ain't' from 'good' English, to the point that today the word 'ain't' is not considered proper grammar in any situation, and 'am not' has no acceptable contraction (though you can, of course, say "I'm not").

Still, you can hear the word all the time. It does still mean 'am not', but it can also mean 'is not', 'are not', 'have not' and 'has not' (it's very rare that this can cause confusion). So, also thinking about how double negatives are not acceptable in standard 'proper' English but can often be used informally, we can see how 'ain't' is used in a few examples:

1. '*I ain't your girlfriend.' = 'I am not your girlfriend.'
2. '*He ain't coming home.' = 'He isn't coming home.'
3. '*Ain't you heard the news?' = 'Haven't you heard the news?'
4. '*There ain't no reason to cry.' = 'There isn't any reason to cry.'

Note that we can't use 'ain't' in place of all negative contractions. '*I ain't drink wine' or '*She ain't be home tonight until 10:00' would be incorrect sentences, not merely non-standard ones.

Exercise:

All of these sentences use the word 'ain't'. How would you write these sentences in standard English, i.e. the kind of English that is acceptable in writing and in English lessons?

1. Your mother ain't going to be happy about this.
2. We ain't finished with you yet.
3. There ain't enough time today.
4. Ain't that my luck?
5. I ain't allowed to stay out past 10:00.
6. Ain't you ever eaten shrimp?
7. She ain't got no bed to sleep in.
8. If it ain't broken, don't fix it!
9. Playing tennis ain't my idea of a good time.
10. It ain't acceptable to use slang words in English grammar class.