Apostrophes that do two jobs
English · Key Stage 2 · The School
Job one: something is missing
Do not becomes don’t. The apostrophe stands exactly where the o was taken out. Cannot becomes can’t; I will becomes I’ll; they are becomes they’re. To place it, ask which letters vanished, and put the mark in the gap they left. Not near the gap — in it.
Job two: something belongs to someone
The dog’s bowl means the bowl belonging to the dog. Add an apostrophe and an s to the owner: Sara’s book, the teacher’s desk. If there are several owners and the word already ends in s, the apostrophe goes after it: the dogs’ bowls means more than one dog.
Plurals never take one
Three apples. Not three apple’s. The commonest apostrophe error in English is putting one in front of an s that simply means “more than one”. Before writing the mark, ask: is a letter missing, or does something belong to somebody? If neither, there is no apostrophe.
The one exception worth memorising
It’s means it is. Its means belonging to it — the dog wagged its tail. This looks backwards, because everywhere else an apostrophe signals belonging. The reason is that its follows his and hers, which take no apostrophe either. Test it by reading “it is” aloud: if the sentence still works, use it’s.