giải giúp em với ạaaaaaaaa

Here are the rewritten sentences: 2. She started working here last year. She has been working here for a year. 3. We began eating lunch when it started to rain. We have been eating lunch for a while. 4. I last had my hair cut when she left me. I haven't had my hair cut since then. 5. The last time he met me was 5 months ago. He hasn't met me for 5 months. 6. It is a long time since we last met. We haven't met for a long time. 7. When did you have this computer? How long have you had this computer? 8. This is the first time I had such a delicious meal. I haven't had a meal as delicious as this before. 12. Linda hasn't had her teeth checked since last year. The last time Linda had her teeth checked was last year. 13. Michelle began to collect stamps in 2015. Michelle has been collecting stamps since 2015. 14. When did they start opening this shopping center? How long has this shopping center been open? 15. I haven't been to the zoo for over a year. The last time I went to the zoo was over a year ago. 16. She began to play tennis 2 years ago. She has been playing tennis for 2 years. 17. She began to play tennis in 1990. She has been playing tennis since 1990. 18. It began to rain 3 hours ago. It has been raining for 3 hours. 19. It began to rain at 3:30. It has been raining since 3:30. 20. This is the first time she has seen the film. She has never seen the film before.