21. I have learned Japanese _________ 3 months. * 1 điểm since for Đây là một câu hỏi bắt buộc 22. May has been working for a non-profit organization _________ I graduated. * 1 điểm since for 23. Kim has been unemployed _________ half a year. * 1 điểm since for 24. I miss my friend. I haven’t seen her _________ months. * 1 điểm since for 25. We have lived in the dorm _________ our first year at university. * 1 điểm since for 26. Jim and Jane have known each other _________ quite a long time. * 1 điểm since for 27. The baby’s hungry. He hasn’t eaten anything _________ the morning. * 1 điểm since for 28. Have you used this laptop _________ 4 years ? * 1 điểm since for 29. They’ve been close friends _________ they started college. * 1 điểm since for 30. My grandmother has been a vegetarian _________ several years. * 1 điểm since for