问题
填空题
光从真空射入某种介质发生折射时，入射角θ1的____________和折射角θ2的____________之比，叫做这种介质的折射率，表达式为n＝____________。任何介质的折射率n____________1（选填“＞”或“＜”）。
答案
正弦（或sinθ1）；正弦（或sinθ2）；
；＞
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光从真空射入某种介质发生折射时，入射角θ1的____________和折射角θ2的____________之比，叫做这种介质的折射率，表达式为n＝____________。任何介质的折射率n____________1（选填“＞”或“＜”）。
正弦（或sinθ1）；正弦（或sinθ2）；；＞
阅读下列短文，根据所读的内容在文章后的表格中填入恰当的单词。注意表格中的每个空格只填1个单词。 注意：每个空格只填1个单词 Although most of us have been learning English for more than three years or even more, we still doubt whether every one of us has already known how to learn English well. Some students still think that learning English is just to remember new words, phrases, grammar rules and some sentence structures. It seems if we do so, we can have a good knowledge of English. We must make sure that things are not always what they seem to be. Now imagine how we learn our mother tongue well. We learn it well by communicating with the people around us all day long. So we think it’s not difficult for us to learn our mother tongue. Why do we think it is hard to learn English well? We all know that learning English usually takes place in schools and there are few opportunities to communicate with other speakers of the language. As a result, some think that learning English is slow and much difficult. It’s because we spend less time learning and practicing it than doing our mother tongue. The following may help us in some way. We should gain confidence and we must be brave enough to speak English before others. Don’t be afraid of losing our faces while talking with others in English. We must make a long and careful study plan. Once we do it, we must take pains to continue learning English every day. Think about what we have done and decide to study English harder than ever. Finally we should take every opportunity to practice speaking English as often as possible. Title: ___小题1:___ to Learn English Well
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