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truonghead2k5
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cho hbh abcd có ab=6, ad=8. trên cạnh cd lấy điểm e sao cho ed=4.đường thẳng ae cắt bd tại o và cắt đường thẳng bc tại f a chứng minh tam giác ade và tam giác fba đồng dạng với nhau b tính od/ob và bf c cmr oa^2=oe.of d gọi k là giao điểm của đường thẳng be và df. tính fk/dk
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UNIT 8 I. Find the word which has different stress pattern from the others. 1. A. coffee B. rupee C. trainee D. agree 2. A. symbolise B. Taiwanese C. guarantee D. kangaroo II. Find one word that does not belong to each group. 1. A. Chinese B.computerese C. Japanese D. Portuguese 2. A. international B. local C. national D. natural 3. A. Awesome B. Great C. Fantastic D. Sure 4.A. scenery B. landscape C. culture D. view 5.A. desert B. haunted castle C. loch D. puzzling world III. Complete the sentences with words/ phrases from the native speaker the USA official language summer camp English speaking countries accents 1. Last year I had a wonderfull time at a ............................. in Britain 2. The USA, the United Kingdom and New Zealand are all ................................................ 3. Australia are............................... of English because they use it as their mother tongue. 4. ................. is in the mid-north of America. 5. Usually, poeple from different parts of a country speak their language with different................... 6. English is an............................... in countries like India, Malaysia, and Singapore. V. Supply the correct tense of the words given in each blanket. 1. Four countries ______________ (visit) by John so far. 2. London ______________ (have) a population of eight million people. 3. The Statue of Liberty in New York is a monument which ______________ (symbolize) freedom. 4. Vietnam’s Independence Day ________________ (celebrate) on September 09 th . 5. We ______________ (visit) Sydney Opera House for several times. 6. Some activities ______________ (prepare) to celebrate the lunar new year now. VI. Choose the correct answer A, B, or C to complete each of the sentences. 1.Alaska is perhaps the most …………… state in the USA. It has over three million lakes. A. puzzling B. festive C. amazing 2.The old tradition of first- footing is still practiced today in …………………….. A. Scottish B. Scots C. Scotland 3.In Canada, the serving of coffee at the end of an evening is a signal that it is time for ……….. A. visitors B. tourists C holiday makers 4.The Maori in New Zealand greet each other by ……………………….. their noses. A. punching B. touching C. blowing 5. Australia is composed of seven ………………….. A. nations B. countries C. states 6.There is a red maple leaf on the ………………… of Canada. A. flag B. banner C. money VII. Read the passage and answer these questions below: England is not a large country. No town in England is very far from the sea, and many English families spend their summer holidays at the seaside. There are no high mountains in England, no very long rivers and very large forests. There are many towns in England. No town is very far from another. The English countryside between the towns is like a carpets of many colors. In Spring and summer, the fields, meadows and forests are light green or dark green, and the gardens are green , red, blue, yellow and white with flowers. Questions 1.Is England a large country? .................................................................................................................................................. 2. Where do many English families spend their summer holidays? .................................................................................................................................................. 3. Are there many towns in England? .................................................................................................................................................. 4. What is the English countryside like? .................................................................................................................................................. VIII. Rewrite the sentences below without changing their original meaning. 1. Radioactive pollution is very dangerous. It can cause abnormal growth. [since] 2. We did not go to school. It rained heavily . [because] 3. I don’t have much money now, but I want to buy a new computer. If 4. Light pollution happens. There is a change in animals’ living patterns. If 5. Acid rain is dangerous. Trees’ leaves are damaged. [because of]

Saving the Environment: One Home at a Time Pollution can be seen not only throughout the world, but also in our own homes. It comes from household chemicals, the amount of water people use and the waste people produce and throw away. What can be done to stop this pollution? Surprisingly, a person can help save the environment by doing simple things. First, we need to recycle, which allows products to be used over and over again. Recycling can also reduce the number of trees cut down to produce paper products. It takes very little effort. It is not hard to place plastic and glass bottles, aluminum cans and paper in a bin. Anyone can do it. Second, we need to watch the amount of water used at home. It can be conserved by taking short showers instead of baths, repairing leaky faucets, using the dishwasher or washing machine only when fully loaded, or simply turning the faucet off while brushing your teeth. Third, we need to reduce waste. We need to recycle whenever possible, but should also try to use this waste effectively. For example, grass clippings and food scraps can be made into compost for plants. The average person produces 4.3 pounds of waste every day, but we can reduce that amount by recycling and reusing. If we do our part in our own homes, we can help keep the planet from becoming more polluted. Question 21. The word “It” in paragraph 2 refers to A: the number B: effort C: recycling D: cutting down Question 19. In order to save water, we can do all of the following things except _____. A: repair leaky faucets B: turn the faucet off while brushing your teeth C: fully use the washing machine D: take short showers instead of baths Question 20. Recycling helps to reduce waste because_______ A: waste can be recycled and reused B: a person can do it in his home C: an average man produces compost for plants D: plants need to develop Question 17. Pollution is caused from the following sources except A: water from households B: water in rivers C: wastes D: house chemicals Question 18. Recycling can help us A: produce more paper products B: place garbage bins easily C: use products again and again D: never cut down trees

I. Choose the best answer to finish the sentence: 1. Noise pollution can lead to________loss. A. looking B. hearing C. listening D. reading 2. If I________a millionaire now, I________travel around the world. But in fact, I am very poor and have no money. A. were/ would B. am/ will C. were/ will D. am/ would 3. We should wear_______when you go to concerts or other loud events to reduce the effect of noise pollution. A. earphones B. earrings C. earplugs D. ear drops 4. What is the main_______of visual pollution? - Because there are too many advertising billboards. A. effect B. affect C. result D. cause 5. Many animals eat the_______and become sick. A. litter B. energy C. aqua D. temperature 6. Ships spill oil in oceans and rivers. This results________the death of many aquatic animals and plants. A. to B. in C. from D. at 7. The acid rain has caused____________to the trees in this area. A. damage B. advantage C. pollutant D. environment 8. Households________waste into the river so it is polluted. A. damage B. lead C. lose D. dump 9. We have to pay a huge amount of money - three million dong for electricity a month________we turn on the heater all the time. A. because of B. due to C. although D. since 10. Have you come_______solutions to this problem? A. up to B. up with C. to with D. on to II. Word form: 1. The____________fish are floating in the water. DIE 2. Do you know what_____________cause air pollution? POLLUTE 3. The river is________________by the dumping from nearby factories. CONTAMINATE 4. Noise pollution can also lead to headaches and high blood____________. PRESS III. Rewrite sentences by combining two sentences into one sentence and using suggested clues: 1. The air is so dirty. I sneeze so much. CONDITIONAL SENTENCE TYPE 2 _________________________________________________________________________ _______ 2. Their children have birth defects. The parents were exposed to radiation. BECAUSE _________________________________________________________________________ _______ 3. The air pollution causes breathing problems. LEADS IV. Choose the answer. 1-Lan is……..beautiful……..clever. a-so / that b-enough / to c-both / and 2-What do you intend………..? a-to buy b-bought c-buying 3-My grandfather stopped………..cigarette. a-to smoke b-smoked c-smoking 4-Tim is old enough……….with machines. a-work b-working c-to work 5-I wish I…………play football like Ronaldo. a-can b-could c-am able to 6-How many people took part……….the contest. a-at b-in c-on 7-The village…………….noisy. a-is become b-is becoming c-are becoming 8-She told me……..these books to her house. a-to take b-take c-taking 9-Mary is looking………her school bag. a-for b-of c-with 10-Susan has worked for that company………..4 years. a-Since b-during c-for V. Write the correct of each verb in the brackets to complete the following sentences. 1. We all adored (1.do)_____ aerobics when we were young. 2. 30 years ago, we (2.not have)________ mobile phone. 3. The girl (3.cry)_____ when a fairy (4.appear)______. VI. Rewrite or combine the sentences, using the suggested words. 1.Vinh really loves to hang out with his friends. => Vinh really enjoys……………………………………………………………… 2. Playing beach games is very interesting. => It is…………………………………………………………………………… 3. Most ethnic peoples in Vietnam speak their own languagues ( Make question) =>…………………………………………………………. 4. The girl worked hard. Her step mother wasn’t happy ( use Although) =>………………………………………………………………..…..

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