Câu 15:Lưu huỳnh có các mức oxi hóa là: A. +1;+3;+5;+7. B.-2,0,+4,+6. C.-1;0;+1;+3;+5;+7. D.-2;0;+6;+7.

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BÀI 1 : The English language is the most widely spoken language in the world. It is usedas either first or second language ……………….. (1) many countries. During the 16th century, only about two million people spoke English. All ……………….. (2) them lived in what is now the United Kingdom. Over the centuries,as a result of various historical events, English has spread throughout ……………….. (3)world. Today, about 400 million people speak English as their native ……………….. (4). Most of them live in Australia, Canada, the United Kingdom, Ireland, NewZealand, South Africa, ……………….. (5) the Unites States.About 100 million people, chiefly living in Bangladesh, India, Pakistan and inmany African ……………….. (6), speak English in addition to their own language. Anadditional 200 million people in the world probably know ……………….. (7) leastsome English. English is really an international language. BÀI 2 In the world today there are 5,000 to 6,000 living languages, of which English is the most widely used. As a mother tongue, it ranks second only to Chinese, which is little used outside China. English is the most international of languages. It is used as the language of aviation, international sport and pop music. Sixty percent of the world’s radio stations broadcast in English, and more than half of the world’s scientific papers are printed in English. It is true that a great number of people are involved in the use of English. To people in Africa, Asia, and South America, English is an important foreign language to master. In most countries in the world, the English language is used as the language of business, commerce, and technology. English is now an effective medium of international communication. However, it is the written English which is not systematically phonetic, that causes difficulties to non-native speakers. 1. Which language is used as the language of aviation, international sport and pop music? 2. Why is English an important foreign language used in 3. What difficulties may learners of English be confronted with?Why? 4. Name three countries in which English is spoken as a first language. 5. As a mother tongue, why does English rank second only to Chinese? BÀI 3 1. is/ but/ not/ Canberra/ the/, / is/ Australia/ capital/ of/ Sydney. 2. Maori/ native/ of/ New Zealand/ people/ the/ are/ the/ Island/ in/ 3. Washington D.C/ opens/ Museum/ a.m./ at Children’s/ in/10.00/National/ The. 4. monument/ San Francisco/ Bridge/ of/ The/ an/ iconic/ Gate/ is/ Golden. 5. its/ years/ language/ for/ considered/ Malaysia/ as/ has/ official/ English. BÀI 4 English is the (1)___language of the Philippines. English-medium education (2)____ in the Philippines in 1901 afterthe arrival of some 540 US teachers. English was also chosen for newspapers and magazines, the media, and literary writing. The latest results from a rent survey suggest that about 65 percent of the (3)____of the Philippines has the (4)___to understand spoken and (5)______English, with 48 percent stating that they can write standard English. The economy is based on English, and successful workers and managers are fluent (6)____English. (7)______ , many schools know that their (8)____must be fluent in English to be successful