题目

Sun Yueming is from China. He is fifteen years old and he is going to England for two weeks to improve his English. He is a camper at the International English Summer Camp for middle school students. He takes a plane and meets other students in Beijing who are going to the same place. He’s quite happy—two of friends are also going to Oxford but they are staying with different families.                           The arrival Oxford is a very famous university town, not far from London. There are beautiful houses and colleges, sports centers, a lot of shops and 将一根洁净的铁丝插入盛有稀硫酸的试管中，可以观察到铁丝表面    ，溶液的颜色由    色逐渐变为    色，反应的化学方程式是    ；在日常生活中要避免铁制容器与    接触，以防止铁制品被    ．