21. As she ________ a letter last night, the lights suddenly ________ out. A. was writing/ went B. wrote/ went C. was writing/ was going D. writes/ went 22. How ________ since we ________ school? A. are you/ left B. will you be/ had left C. have you been/ had left D. have you been / left 23. I ________ my uncle’s home many times when I ________ a child. A. visited/ is B. visits/ was C. visited/ was D. visited/ were 24. It ________ me half an hour to get to the supermarket yesterday. A. take B. takes C. took D. spent 25. If I were you, I ________ him as my nephew. A. will treat B. would treat C. will have treated D. am treating 26. I can’t believe that my expensive bicycle ________ last night. A. was stolen B. was stealing C. is stolen D. stole 27. I ________ here for more than 10 years. A. have taught B. taught C. teach D. is teaching 28. As I ________ my homework, he came yesterday afternoon. A. did B. were doing C. am doing D. was doing 29. At this time yesterday, everyone ________. in the room. A. is dancing B. was dancing C. dances D. danced 30. After Mary________ her degree, she intends to work in her father's company. A. will finish B. is finishing C. finishes D. will have

√a ²+2 √a ²-1 - √a ²-2 √a ² -1 với a=√5

11. He said that everything ________ all right A. is B. would be C. will be D. can be 12. Each of you ________ a share in the work A. have B. having C. has D. going to have 13. How many times________ them so far? A. have you seen B. did you see C. were you seeing D. had you seen 14. Please send our regards to Tom as soon as you ________ in New York. A. will arrive B. is going to arrive C. arrive D. arrived 15. By the time the ambulance approached, the man________. A. would die B. had died C. died D. dies 16. We________ for going home when it began to rain A. has prepared B. are preparing C. will be preparing D. were preparing 17. I haven’t seen him for months. A. It’s months since I last saw him B. It’s months when I last saw him C. It’s months before I last saw him D. It’s months after I last saw him 18. Tim________ his hair while I ________ up the kitchen A. washed-was cleaned B. was washing-was cleaning C. was washing-cleaned D. washed-cleaned 19. Working for 12 hours a day ________ her very tired. A. makes B. made C. make D. making 20. I am so happy to hear from Mary because I haven’t seen her ________ last year. A. for B. on C. since D. later

chứng minh rằng với mọi n chẵn A=n^3-76n chia hết cho 48

Vẽ bé đậu mầm cute Nl: vui vì nhận đc quà từ hoidap

Pt đa thức thành nhân tử (x+2)(x+3)(x+4)(x+5)-24

Tính các góc của ΔABC biết 4 ∠A ; 6 ∠B; 3 ∠C tính góc A góc B góc C Giair thích giùm cho ạ. Cảm ơn trươc nha :3

Pt đa thức thành nhân tử (x+2)(x+3)(x+4)(x+5)-24

Giúp mình với hôm nay mình phải nộp rồi

Anh chị có đồng tình với quan điểm của tác giả trong 2 dòng thơ in "anh không thể chỉ đấm say đứng nhìn Anh phải là một nét vẽ dẫu đơn sơ "