What's this unit about? - Unit 9. Changes.

This unit is about how you, someone in the class or in your family, your school, your house
 or your town have changed, and also about things related to school.

We are going to introduce the present perfect to talk about actions that started in the past,
but continue in the present, have some effects in the present or when the time is not
mentioned. We also use this tense with ever and never to talk about experiences.