1. Has my father been working here for five years? 2. Has my father been working here for five or six years? 3. Who has been working here for five years? 4. What has my father been doing here for five years?  5. My father has been working here for five years, hasn't he?

1. Does he work here five days a week? 2. Does he work five or four days a week? 3. Who works here five days a week? 4. Where does he work five days a week? 5. He works here five days a week, doesn't he?

1. Are they revising the material for the exam? 2. Are they revising or learning the material for the exam? 4. Who is revising the material for the exam? 5. They are revising the material for the exam, aren't they?