1. Câu cần sửa: "I have sent an email to Jack last week, but he hasn't replied." Câu sửa: "I sent an email to Jack last week, but he hasn't replied." 2. Câu cần sửa: "I feel at home in this village because we lived here for six years now." Câu sửa: "I feel at home in this village because we have lived here for six years now." 3. Câu cần sửa: "I'm a big football fan, but I have been never the stadium." Câu sửa: "I'm a big football fan, but I have never been to the stadium." 4. Câu cần sửa: "He is receiving treatment in cancer." Câu sửa: "He is receiving treatment for cancer." 5. Câu cần sửa: "We need some cholesterols to help our skin, brain, and other organs grow, but too much of it can cause health problems." Câu sửa: "We need some cholesterol to help our skin, brain, and other organs grow, but too much of it can cause health problems." 6. Câu cần sửa: "Your body may not be able to fights infections naturally if your immune system is weakened." Câu sửa: "Your body may not be able to fight infections naturally if your immune system is weakened." 7. Câu cần sửa: "I told him that if I drank coffee before bedtime, I can't sleep." Câu sửa: "I told him that if I drink coffee before bedtime, I can't sleep." VI. Sắp xếp lại các câu: 1. "She often takes paracetamol if she gets a bad headache." 2. "How many calories do you burn doing aerobics for 2 hours?" 3. "Getting enough sleep helps students do their best in the classroom." 4. "The organization believes that sport helps young people in other areas of their lives."