How do you spend your time at school? Do you know how students in other countries study every day? Here are the studying ways in some western schools.

American Students

    American students spend seven hours in their schools every day. And the day is divided（划分） into classes of about 40 to 50 minutes. Students study English, history, math, science, art and foreign languages. They go to listen to different lessons taught by different teachers in different classrooms. After class they learn job skills. Sometimes they study by working in an office, a hospital or other places one day a week.

German Students

    German students love practicing. Lots of schools have lessons for only half a day. They spend most time practicing. Teachers give students enough freedom. Students may try all kinds of ideas they have. They begin to plan what they will do in the future and work hard at a young age.

French Students

    French students like independence（独立） and freedom. Their school life is very relaxing and interesting. When they have tests, they may have snacks. For example, they can put a few desks together, and put some peanuts （花生）or candies on them.

亚洲河流中，长河众多，且呈放射状流向周边的海洋，源远而流长。在亚洲有很多条国际性河流，同一条河流在不同的国家有不同的名称。下列选项中两种河流名称所指的是同一条河流的是（    ）

玻璃容器被下列物质沾污后，需要洗涤．如洗涤方法属于物理方法的，请写出所需试剂；洗涤原理属于化学反应的，写出有关反应的离子方程式；若无法用试剂使容器复原者，请说明原因．