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Easy Ways to Improve Your Writing Skills     For better or for worse, school is filled with writing homework. Good writing is important for getting a good grade.  36  Luckily, anyone can improve his or her writing with the right guidance and a little practice. Here are four easy tips to help you improve your writing skills: 1. Organize your thoughts first. Good writers outline their thoughts before starting putting their pens to paper or hands to a keyboard. Firstly, write out each main topic. Next, list subtopics(小标题) beneath much main topic. Lastly, put the topics and subto13．某化学兴趣小组的同学来到实验室准备做制取气体的实验，如图是实验室制取气体常用的装置：（1）请你告诉小红同学，如图中标号仪器的名称a试管b分液漏斗．（2）小雨同学打算用加热高锰酸钾的方法制取氧气．该反应的化学方程式是2KMnO4$\frac{\underline{\;\;△\;\;}}{\;}$K2MnO4+MnO2+O2↑，其发生装置应选A．（填字母标号，下同）（3）小丽想用大理石和稀盐酸反应制取CO2，那她应该选择的气体收集装置是D；若要制得干燥的CO2，还应将气体通过F装置．