Which ones are wrong?

1. The recession in the U.S. has had a big effect on banking.
2. Racquet technology has had a big effect on tennis.
3. You dress more warmly than me.
4. Do your parents have a credit card?
5. Does your parents have a credit card?
6. Does your parent have a credit card?
7. That is my most favourite song.
8. The education system has had a big effect on how English is taught.
9. I have 4 people in my family.
10 There are 4 people in my family.
11. I have 4 sisters in my family.
12. There are 4 sisters in my family.
13. I have 1 sister in my family.
13. There is 1 sister in my family.
14. Does your mother have a credit card?
15. Does your mother and father have a credit card?
16. Do your mother and father have a credit card?
17. Do your mother and father both have a credit card each?
18. Do your mother and father have a credit card each?
Cheers Fulvio