Ответ:

Вы: Hi, it's (ваше имя) here! Have you done your homework?

Ваш друг: Yes, I have. Why did you ask?

Вы: My family and I are going to the museum. Do you want to come with us?

Вд: I don't mind, but…will your brother be with us?

Д: Oh, I forgot, that you don't like him. But, don't be upset: there also will be my stepsister.

Вд: Stepsister?

Д: Yes, she have a long blonde hair and green eyes.

Вд: Wow, I think she's pretty nice!

Д: Okay, so lets meet in a front of our school.

Вд: Good, bye!

Д: Bye!

надеюсь, всё правильно, удачи!