Bonjour
En anglais l'adjectif possessif s'accorde avec le possesseur (celui qui possède) et non avec ce qui est possédé comme en français.
1- She invited everyone to her house.
2- He didn't want to take his car so we took ours.
3- I have started my own business.
4- People are only interested in their own affairs.
5- My business is doing well. What about yours ?
6- Has she told you about her plans ?
7- John's ideas are very similar to mine.
8- We've put our plans on hod but Sue and Rob are going ahead with theirs.
bonne fin de soirée ☺☺☺