Người ta cần truyền một công suất điện 24000W ở hiệu điện thế 50kV bằng dây dẫn có điện trở 5ôm a/ tính công suất hao phí trên đường dây b/ tính công suất hao phí trên đường dây khi sử dụng hiệu điện thế 500kV

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I. Complete the sentences using the past simple form of the verbs. 1- I (was).......................................a student 2 years ago. 2- He (was).................................. a doctor two years ago. 3- They (were)................................. farmers last year. 4- Lan and Ba (were) .........................nurses last year. 5- It (was not)............................ cold yesterday. 6- She (was not)........................a pupipl last week. 7- This hat (was not) .........................new yesterday. 8- My parents (were not) .......................teachers two years ago. 9- He (was not) ..........................a mechanic last Monday. 10- (was)................... he an engineer yesterday. No , he (wasn’t)..................... 11- (was) .................It hot last week? 12- The windows (were) ....................open last Monday. 13- (were)................. you a teacher two years ago? Yes , I (was)................. 14- Where (was) ....................Nam from yesterday? 15- Why (was) ............................he unhappy last Tuesday? II. Complete the sentences using the past simple form of the verbs. 1. I (went)........................ to Nha Trang two years ago. 2. Ba (played)............................. football yesterday. 3. I (ate) ..........................a lot of fish yesterday. 4. Her aunt (took)................................... her to see Cham Temple last year. 5. Tuan (had).............................. a new bike yesterday. 6. She (didn’t buy).................................. a new ruler yesterday 7. He (did not talk)................................. with his parents about his vacation in Da Lat last year. 8. They (did not come).................................. school yesterday 9. The windows (did not close)............................ yesterday? 10. We (did not return) ......................................at home at 7 pm last Monday. 11. She (did not eat ) .............................................fish and crab yesterday. 12. Lan (did not go )................................. Ho Chi Minh city two years ago. 13. My parents (did not take).................................to Vung Tau last week. 14. We (did not have)......................................a lot of friends in Ha Noi. 15. Were Lan and Hoa ................................... your school two years ago? 16. What did they (play) ...............................last week? 17. What did Hoa (try)...................................................... on yesterday? 18. Who (talked) ....................................to about the film on TV last Monday? 19. Where did they (stop .....................................on their way back last Sunday? 20. What did the student (wear)...................................... at school two years ago? III.Complete the sentences using the past simple form of the verbs. 1. I _____ at home all weekend. ( stayed) 2. Angela ______ to the cinema last night. (went) 3. My friends ______ a great time in Nha Trang last year. (had) 4. My vacation in Hue ______ wonderful. (was) 5. Last summer I _____ Ngoc Son Temple in Ha Noi. (visited) 6. My parents ____ very tired after the trip. ( were) 7. I _______ a lot of gifts for my little sister. (bought) 8. Lan and Mai _______ sharks, dolphins and turtles at Tri Nguyen aquarium. (saw) 9. Trung _____ chicken and rice for dinner. (ate) 10. They ____ about their holiday in Hoi An. (talked) 11. Phuong _____ to Hanoi yesterday. (returned) 12. We _____ the food was delicious.(thought) 13. Yesterday, I (went)______ to the restaurant with a client. 14. We (drove) ______ around the parking lot for 20 mins to find a parking space. 15. When we (arrived) ______ at the restaurant, the place (was) ______ full. 16. The waitress (asked) ______ us if we (have) reservations. 17. I (said), "No, my secretary forgets to make them." 18. The waitress (told)______ us to come back in two hours. 19. My client and I slowly (walked) ______ back to the car. 20. Then we (saw) ______ a small grocery store. 21. We (stop) in the grocery store and (bought) ______ some sandwiches. 22. That (was) ______ better than waiting for two hours. 23. I (did not go) ______ to school last Sunday. 24. Did She (get) ______ married last year? 25. What did you (do) ______ last night? - I (did) ______ my homework. 26. I (loved) ______ him but no more. 27. Yesterday, I (got) ______ up at 6 and (had) ______ breakfast at 6.30.