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Hello,

Maybe you can help me (not native to english) explain why I place an apostrophy AFTER the S when I write for example: in 10 years' time or with my parents' permission.

Does it stand for my parents their permission but I can not write parents's ? (theirs) If so, how does one explain the 10 years' time ? I hope someone can explain this to me.

Thank you very much.
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In thge possessive form, if the name's in the plural with an -s, you just add the ' . If the plural doesn' t end with an S, you have to add the 's.

The children's room, but my parents' car.
Comments  
In the possessive form, if the noun is plural, or already ends in -s, just add:' (an apostrophe). e.g. the girls' room.

For names ending with an s, both the ' and the 's are accepted e.g. James' coat or James' s coat.

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 pieanne's reply was promoted to an answer.
AnonymousDoes it stand for my parents their permission but I can not write parents's ? (theirs) If so, how does one explain the 10 years' time ? I hope someone can explain this to me.

Just wanted to add: you may also find some words ending with -s followed by the 's.

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