Each of these sentences has one mistake. Please correct them.
a. Do you know this dog? He is very cute.
b. I don’t know nothing about what is going on.
c. This books belong to you.
d. I’m thinking about buying hers a new dress.
e. There isn’t something to eat in the fridge.
f. Henry and me are best friends.
g. They are looking at themself in the mirror.