题目

以下式子化简正确的是（ ） A . －（x－3）=－x－3 B . 4(a＋b)＋2(a＋b)－(a＋b)=5(a＋b) C . －5(－1－0.2x)=－5＋x D . (a＋b)＋(a－b)－(－a＋b)=3a+b 答案：BLearners of English, especially self-taught learners may have trouble in understanding speeches by native speakers. The following ways might help improve their listening ability. First of all, do things step by step. It is not good to listen to something beyond your level. Better choose a suitable course and start with the first book. Go on to the second book only after you are sure you understand the first one. Secondly, stick to one course of study. Don’t change books often. Never let your attention be attracted by another course just because it seems to be more “fashionable”.  Thirdly, listen to the English news program over the radio from time to time.  Better go through the news stories in the Chinese-language newspaper first. That will make it easy for you to understand the English news on the radio. Fourthly, if you have time, listen to some interesting stories in “Special English from the V.O.A. or other listening materials of the same level as that of your textbook”. 1.This is a piece of advice to learners of English on how to ________. A．improve their listening ability B．read fast C．write better English and read faster D．speak correctly 2.If you want to understand the English news program on the radio, you should ________. A．read the Chinese-language newspaper step by step B．read again and again the Chinese-language newspaper C．go through the Chinese-language newspaper first D．be able to recite the Chinese-language newspaper 3.The author advised that once you have taken up a course, you ________. A．should stick to it B．should begin with the last book C．should take up other courses if they are more fashionable D．shouldn’t do anything else 4.In this passage, V.O.A. stands for ________. A.  a book         B. a magazine       C. a text-book      D. a radio station