Viết lại câu :
1. If you don’t water these plants, they will die. → Unless
2. The questions were so difficult that we couldn't answer all of them. → They were
3. I don't know her phone number, so I can't call her. → If
4. The last time I spoke to him was four months ago. → It's
5. "Why don't you have a doctor check your eyes, Mary?" → Susan suggested
6. The astronauts orbited the earth in two hours. → It took
7. "Don't forget to bring along the rainçoat," Thuy's grandma said. → Thuy's grandma reminded
8. “Should I apply for this scholarship?" said Jane. → Jane wasn't sure
9. Phong studies the best in our class. → No one studies as
10. Do you find it difficult to understand him? → Do you have
11. Driving a big car was a new experience. → I wasn't used
12. "How much are the course fees?" she asked me. → She asked
13. When did you start playing for the national football team? → How long
14. He plays the guitar for a small group because he wants to earn some extra money. (in order that)
15. Will you take care of the parrot while I am away? (look)
16. I am very excited about seeing you next week. (looking)
17. I'm sorry I don't know her address. → I wish
18. May I turn on the television? → Do you
Dẫn 6,72 lít một hỗn hợp khí gồm hai hiđrocacbon mạch hở (không phải mạch vòng) qua dung dịch brom dư sao cho phản ứng xảy ra hoàn toàn. Sau thí nghiệm, thấy khối lượng bình đựng dung dịch brom tăng thêm 5,6 gam, đồng thời thoát ra 2,24 lít một chất khí. Mặt khác, nếu đốt cháy toàn bộ 6,72 lít hỗn hợp trên thấy tạo ra 22 gam CO2 và 10,8 gam H20. Biết các thể tích khí đo ở đktc. Xác định công thức phân tử của hai hiđrocacbon