Hai người thợ cùng làm một công việc thì sau 16 giờ hoàn thành. Nếu hai người làm chung trong 3 giờ sau đó người thứ nhất nghỉ và người thứ hai làm một mình trong 3 giờ nữa thì cả hai người làm được 25% công việc. Hỏi làm riêng thì mỗi người phải làm trong bao lâu sẽ hoàn thành công việc?

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I. Choose the word whose underlined part is pronounced differently from the others. 1. a. myth b. cycling c. itchy d. allergy 2. a. headache b. spread c. health d. weak 3. a. fat b. leaf c. of d. safe 4. a. flu b. sunburn c. junk d. much 5. a. wash b. wear c. wake d. wrap II. Choose the odd one out. 1. a. running b. coughing c. cycling d. swimming 2. a. vegetables b. fish c. fried chicken d. fruits 3. a. cold b. cough c. stuffy nose d. sunburn 4. a. soda b. milk c. fruit Juice d. water 5. a. fever b. health c. obesity d. headache III. Choose the best answer a, b, c, or d to complete the sentence. 1. Please wake me ________ at 5 and we will leave at 6 in the morning. a. up b. on c. over d. in 2. If you want to ________ weight, you should follow a low-fat diet. a. lose b. gain c. put on d. take 3. Junk foods are high in fat, sodium and sugar, which can lead to ________. a. fever b. allergy c. obesity d. stomachache 4. He looks so ________. He can’t keep his eyes open! a. happy b. tired c. healthy d. fit 5. If you want to stay healthy, eat ________ vegetables, whole grains, fruit and fish. a. much b. fewer c. more d. less 6. Fruit tastes good ________ it’s healthy for your body. a. so b.but c. or d. and 7. You are ________ you eat, so don’t eat unhealthy foods. a. what b.who c. which d. that 8. She looks very tired. She should work ________ or she will get sick. a. well b. less c. more d. enough 9. She stays in ________ by exercising daily and eating well. a. health b. fit b. size d. shape 10. Don’t sit too close to the screen, ________. a. and you’ll hurt your eyes b. so you can see more clearly c. or you’ll get a headache d. but it’s bad for your health