题型:阅读理解 题类:模拟题 难易度:普通
安徽省"江南十校"2019届高三英语冲刺联考(二模)试卷
When you think back to the blackboard from your school days, what color is it? Chances are that it's green. So what's up with the name? Originally, blackboards were really black. Before wall-sized blackboards existed, late 18th-century students used their own mini boards made of slate (石板) or painted wood, according to Concordia University, Those first boards were, in fact, black, and they paved the way for the larger ones.
In 1800 when a Scottish headmaster named James Pillans wanted his students to draw maps, the students couldn't draw the maps their teacher wanted on their tiny boards, so Pillans put several slates together to create a large board. Problem solved! From there, the idea spread quickly as teachers could finally show a concept to the whole class at one time. By 1815, the massive writing spaces were common enough to earn their own name: blackboard.
The color change came in the 1960s when companies sold, steel plates, coated with green enamel (漆) instead of the traditional dark slate. The new material was lighter and less fragile than the first blackboards, so they were cheaper to ship and more likely to survive the journey. Teachers weren't complaining either. After all, the new "greenboards" made the chalk powder easier to erase. Plus, the enamel left less of a glare and the color was nicer to look at. At that point, people started using the word "chalkboard "as a more accurate descriptor, but "blackboard" still stuck around.
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