20. This is the first time she has seen this film. She has not ................................................................................................................. 21. When did they begin doing their homework? How long .................................................................................................................... 22. They haven’t published this book for many years. They ........................................................................................................................... 23. My cousin began to play the violin one year ago. My cousin has............................................................................................................. 24. The boys have played football since 2 o’clock. The boys started ......................................................................................................... 25. It has been 10 years since we started to live here. We have...................................................................................................................... 26. It has rained since I got up this morning. It began....................................................................................................................... 27. How long have they lived in this new house? When .......................................................................................................................... 28. She hasn’t ridden a bike since the first day of March. She last ....................................................................................................................... 29. John began investigating the case a week ago. John has...................................................................................................................... 30. We have learnt Chinese since we were young. We started...................................................................................................................