21. Workers are building many new roads in this city. ​​(Passive voice: Chuyển sang câu bị động) à …………………………………………………………………………………………………………… 22. They have changed the date of meeting. ​​(Passive voice: Chuyển sang câu bị động) à …………………………………………………………………………………………………………… 23. I was sick yesterday, so I didn’t go to class. ​ à If ………………………………………………………………………………………………………… 24. I can’t look the word up because I don’t get a dictionary. à If ………………………………………………………………………………………………………… 25. Today isn’t Sunday, so I can’t go out with my friends. à If ………………………………………………………………………………………………………… 26. We didn’t find out about the meeting until he phoned us. à It was not until …………………………………………………………………………..……………… 27. I didn’t know how to ride a bicycle until I was 15. à It was not until …………………………………………………………………………..……………… 28. Tan / be / interest / astronomy. (Complete the sentence with V-ing/-ed): Hoàn thành câu với động từ đuôi –ing hoặc –ed) à