I realise this should probably be in pedants' corner but I am becoming more and more irritated at so many posters misusing the word 'your'. It's lazy, it doesn't make sense and it's just wrong.
And yes, I'm in a bad mood today.
"If your going to the shops can you buy x,y,z...." NO NO NO. The word is you're! The apostrophe denotes a missing letter and an abbreviation!
You a're.
The word 'your' is possessive. So you could say "If your chauffeur is going to the shops today..." or daughter, or son.
Rant over.