补全对话

A: Mum, I shall not have lunch at home today.

B:         1          ,Linda?

A: I want to go to the pet shops at noon with my classmates. Most of the students in our school have their own pets. Mum, as you know,         2          ?

B: What kind of pet do you want to have?

A: A dog or a cat. I haven't decided yet.

B:         3          .It would make much noise. And a dog has to go out every day, and there isn't a dog near our building. And the dog food is expensive.

A:         4           .Cats are cheaper than dogs, and        5           ,too.

B: Yes, cats are easier to keep.