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qangduy2018
2 năm trước
Bài 1 hoà tan 13,28g hh gồm cu, fe2o3 và fe3o4 bằng 340 ml dd hcl 1M vừa đủ thì thu đc dd B và còn lại 0,64g chất rắn không tan. Tính nồng độ các chất tan có trong dd B Bài 2: hoà tan hh X gồm 3,2g cu và 23,2g fe3o4 bằng lượng dư dd h2so4 loãng thu đc dd y. Cho dd naoh dư vào y thu đc kết tủa z. Nung z trong không khí đến khối lượng ko đổi thu đc m g chất rắn. Biết các phản éng đều xảy ra hoàn toàn. m=?
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Giúp em nhanh với ạ, em đang cần gấp ạ Pronouncing a language is a skill. Every normal person is an expert in the skill of pronouncing his own language; but few people are even moderately proficient at pronouncing foreign languages. There are many reasons for this, some obvious, some perhaps not so obvious. But I suggest that the fundamental reason why people in general doo not speak foreign languages very well is that they fail to grasp the true nature of the problem of learning to pronounce, and consequently never set about tackling it in the right way. Too many people fail to realize that pronouncing a foreign language is a skill – one that needs careful training of a special kind, and one that cannot be acquired by just leaving it to take care of itself. I think even teachers of languages, while recognizing the importance of a good accent, tend to neglect, in their practical teaching, the branch of study concerned with speaking the language. So the first point I want to make is that English pronunciation must be taught; the teacher should be prepared to devote some of the lesson time to this, and should get the student to feel that here is a matter worthy of receiving his close attention. So, there should be occasions when other aspects of English, such as grammar or spelling, are allowed for the moment to take second place. 36. What does the writer actually say about pronouncing foreign languages? A. Only a few people are really proficient. B. No one is really an expert in the skill. C. There aren’t many people who are even fairly good. D. There are a lot of people who are moderately proficient. 37. The writer argues that going about the problem of pronunciation in the wrong way is________. A. an obvious cause of not grasping the problem correctly. B. a fundamental consequence of not speaking well C. a consequence of not grasping the problem correctly D. not an obvious cause of speaking poorly 38. The underlined word “one” in the passage refers to_________. A. skill B. careful training C. special kind D. itself 39. The best way of learning to speak a foreign language, he suggests, is by_________. A. picking it up naturally as a child B. learning from a native speaker C. not concentrating much on pronunciation D. taking on systematic work 40. The underlined word “aspects” in the passage probably means________. A. pronunciation B. parts C. words D. sentences

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