Ответ:

It's — сокращение от it is («это есть»); its — притяжательное местоимение («его/её»).

  1. My house is not new, but it's a good house.
  2. It is a chick. Its tail is short.
  3. What time is it? — It's six o’clock.
  4. This is my new house. Its walls are brown.
  5. Where is your car? — It's in the street.
  6. I can see a box. It's a clean box.