Ответ:

  1. A: We are going shopping. Do you want to come?
    B: I can't. I am helping Mum.
  2. A: Why are you taking the umbrella?
    B: It is raining outside.
  3. A: What do you wear at school?
    B: I usually wear a school uniform, but today I am wearing my jeans and a T-shirt.
  4. A: What are they talking about?
    B: I do not know. I think they are trying to decide what to do tonight.