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Every school day, we use schoolbags to carry all of our things to school. But have you ever thought about the 1 of schoolbag?
In the Han Dynasty, when old-style private (私人的) schools were 2, students used bamboo boxes to carry things to school. There were usually two or three layers (层) in the boxes. Kids put different school things, like blushes and 3 in the boxes. Hundreds of years later, people 4 a new kind of schoolbag called the budai. The budai was not so 5 as the bamboo box so that it was easy to carry. Later in China, military rucksacks (军用帆布包) became 6. Ask your grandparents or parents about these bags. Maybe they can tell you how they 7 used them when they were in school.
A new style of schoolbags has appeared in recent years. Many of them have pictures of cartoons or pop stars on them. They are more 8 to use. Some students have special bags with 9. Students pull them just like pulling a luggage case (行李箱), so that it's easier for them to carry heavy textbooks.
Schoolbags still 10. Can you imagine what future schoolbags will be like?