(Note for parents and teachers: most of the problems children have with punctuation are the result of not being able to read fluently enough to be able to feel the rhythm of what they are writing. When they write, they are unable to keep track of what they have just written, and so they can easily make what look like ridiculous mistakes: they cannot feel where the pauses are because they always hesitate after reading each word anyway, and they often can't feel when they have reached the end of a sentence either for the same reason. There is little point in telling them where to put commas and full stops until they can read reasonably fluently. The basics of punctuation are actually pretty straightforward and are easy to learn, but you have to be a good reader first.)
The Full Stop (known as a Period in American English):-The full stop is used to mark the end of a sentence.
The Question Mark:-Question marks are used at the end of questions, aren't they?
The Exclamation Mark:-Exclamation marks are used to show exclamations, but be careful! Avoid using too many of them, because a page filled with exclamation marks usually gives the impression that it has been written by an idiot, and using two or more exclamation marks together is absolutely forbidden!! On very rare occasions you may get away with breaking this rule, but don't make a habit of it. You are also not allowed to put an exclamation mark and a question mark together because it's horribly ugly. Very occasionally a sentence really does feel that it needs both: e.g. "You bought a dog?!" There are usually alternative ways of getting round the problem: e.g. "You bought a dog?" she exclaimed. However, if a series of questioning exclamations of this type occur in quick succession, it is actually so ugly to say "she exclaimed" every time that it's better just to use an exclamation and question mark together.
The Comma:-Commas tell you to pause for a moment when reading things out, thus separating the different phrases in a sentence to make it easier to understand. Lists always need commas between the things listed there even if they aren't read out with obvious pauses between them, so if you are puting your dog, cat, hamster, horse, elephant and crocodile into a list of your pets, you should remember to put commas between them. Commas, as in this example, can also be used instead of brackets (because it looks much more tidy).
The colon:-Colons are used for a couple of things: one use is to tie two sentences together where the second sentence is an expansion of the idea in the first, while the other use is to introduce a list of items. Notice that if a list is introduced by a colon, then the items in that list are separated by semicolons instead of commas: dog; cat; hamster; horse; elephant and crocodile. If the stuff following a colon is to be shown underneath rather than following on the same line, a dash is tacked onto it, as you can see after each heading on this page:-
The Semicolon:-Semicolons are used in lists of things following a colon (see above), or for longer pauses than a comma. It is very hard to explain where to use semicolons in this second way; usually a colon or full stop can do the same job, though there are occasions where only a semicolon will do; or at least, I think there are.
The dash:-The dash (a little horizontal line) can be used as an alternative to brackets - like this - or it can replace a colon. However, you should avoid using dashes if you can - it is considered to be very bad form to fill your text with them.
The Hyphen:-Some words like "co-operate" look better with a hyphen in them because it tells you that the two vowels don't combine to make an "oo" sound. The hyphen is used for a few standard things like "shoot-'em-up games". There are also many occasions where it is necessary to join two words together with a hyphen to help clarify their role in a sentence, such as in "I saw the bird-eating spiders", which has a very different meaning from "I saw the bird eating spiders". Another use of the hyphen is to split words when they overflow from one line to the next: this should only be done at natural syllable boundaries, so "dis-ad-vant-ag-ed" shows reasonable places to split a word, while "di-sa-dv-a-n-ta-ge-d" shows totally unacceptable places to split it.
The Apostrophe:-The most important use of this is to show that letters have been missed out: "do not" to "don't"; "cannot" to "can't"; "will not" to "won't"; "shall not" to "shan't"; "I am" to "I'm"; "I have" to "I've"; "he is" to "he's"; "he has" to "he's got"; "John is" to "John's"; "John has" to "John's got"; "you are" to "you're"; "they have" to "they've"; "you have" to "you've"; "we will" to "we'll"; etc. Notice that when "shall not" is shortened, shan't only gets one apostrophe, even though you might expect it to have two (sha'n't): this is a little strange, because when "and" is shortened, you get "fish 'n' chips" and "rock 'n' roll".
indentThe other main use of the appostrophe is with "possessive constructions" (when something belongs to someone): John's dog (the dog belonging to John). There is also a little difference between "the boy's dog" and "the boys' dog": in the first case the dog belongs to one boy, while in the second case the dog belongs to two or more boys. The second example is really a shortened form of "the boys's dog", but the second "s" is dropped because it sounds horribly ugly. Some plural words like "children", "people" and "men" don't end in "s", so the "s" after the apostrophe is obviously left in: "the children's dog".
indentBeware of the word "it's": this can only ever mean "it is" or "it has". If you want to talk about the dog's tail, you must write "its tail" rather than "it's tail": the only reason for this seems to be that "its" comes from the special set of words "my, our, thy, your, his, her, its, their" - it therefore does not get the apostrophe which you would naturally expect it to have. Other words to behave in this way are ours, yours, hers and theirs.
indentIt is occasionally necessary to use apostrophes to make words plural, as in: "yesses and no's" and "do's and don'ts". These apostrophes prevent the formation of extremely puzzling words such as "nos" and "dos".
Quotes / Inverted Commas:-If you want to discuss a word, like "example", then you should put inverted commas (") round it. Notice that the ordinary comma follows the inverted commas in this case: this is quite different from the way inverted commas are used when they surround dialogue, as you will see in a moment. It is also possible to use single quotes to highlight a word, like 'penguin', but it is usually best to avoid this as they may be confused with apostrophes. If you want to write a bit of dialogue in a story, just study the formats of the following sentences and copy them.
"You should have put that full stop before the inverted commas," said the teacher. "The inverted commas should always come last when you're using them to indicate speech."
indent"Where abouts?" asked John.
indent"There!" she said, pointing into the scribbled mess in his jotter.
indent"Like with that comma?" he asked.
indent"Yes," she replied, "and it's the same with a question or exclamation mark too." She read silently for a moment. "And that should be a comma; not a full stop!"
indent"But that's the end of a sentence!" protested John.
indent"Ah, but it's not that simple," she explained. "It may be the end of the spoken sentence, but it's not yet the end of the written sentence, so you can't use a full stop there."
indentJohn thought for a moment, and then said, "What a strange system! We have to start a spoken sentence with a capital letter even if it starts in the middle of a written sentence, but we have to end it with a comma instead of a full stop if the written sentence keeps going afterwards! It's mad!"
indent"I suppose it is rather silly," the teacher agreed: "You can actually end a spoken sentence in the middle of a written one with a full stop so long as it's part of an exclamation or question mark, but otherwise it has to turn into a comma. Anyway, that's the way it's done, so you'll just have to get used to it!"
Abbreviations:-The full stop can also be used to show that a long word has been shortened, as in "ctd." which is short for "continued". If a shortened word appears at the end of a sentence, it should technically have two dots after it, but no one ever seems to bother because it looks so silly.
If you follow all the above rules of punctuation, you'll be much better at it than most adults.