题目

Dear students,Behaving well is the 【1】to getting on well with others. As a student, I think it's very important to do everything 【2】 time and keep promises. Never lie to others or say bad words. We should be 【3】 to others and offer to help people in need. We'd better not talk【4】in public. Don't 【5】rubbish on the ground. Remember to obey the traffic rules. David 答案：【答案】【1】secret【2】in【3】polite【4】aloud / loudly/ loud【5】throw【解析】本文是大卫写给同学们的一封信，告诉同学们举止得体是与人相处融洽的秘诀、做每件事要及时和遵守承诺、礼貌待人，主动帮助有需要的人、要在公共场合大声说话、不要把垃圾扔在地上、记住遵守交通规则等等。【1】句意：利用物质的化学性质进行物质区分的是（　　） A、根据气味辨别醋和水B、根据密度的大小，辨别铜和铁C、根据颜色区别氧化铜和氧化镁D、根据是否可以燃烧，区别氢气和氧气