1. i (have been doing/have done) have been doing the flat since 2 o’clock. 2. how long (have you known/have you been knowing) each other? 3. i (haven’t worn/have not been wearing) these shoes yet. 4. mary (has phoned/has been phoning) the office since morning but she (hasn’t managed/hasn’t been managing) to get through. 5. i (have met/have been meeting) mr black only once, i don’t know what kind of person he is. 6. john (has owned/has been owning) the house for 15 years. 7. this factory (has polluted/has been polluting) the air for 12 years. 8. mark is a vet, he (has saved/has been saving) animals for years. 9. mike is not interested in foreign languages. he (has never even tried/has never even been trying) to do it. 10. your mouth is dirty. (have you eaten/have you been eating) jam? 11. a number of students (have waited/have been waiting ) for you in the hall for an hour already. 12. they (have lived/have been living) in this city all their lives and they are not going to leave.
