Underline the right word: 1. That's your / yours problem, not my / mine. 2. I'm going out with some friends of my / mine. They/Their are from Pennsylvania. 3. I'm going to buy Pam/ Pam's car. It / It's seems to be in an excellent condition. 4. Who / Whose key is this? Is it your / yours? 5. Kate's having dinner with a friend of her / hers. 6. Some of my children / my children's toys are lost. 7. My / Mine is broken. James / James's is all right. You can use it / its. 8. I gave my / mine phone number to she/her.