与美国小学生一起学英文第10册 第11期:螺丝钉
时间：2019-01-10 作者：英语课 分类：与美国小学生一起学英文第10册
英语课
Screws 螺丝钉
Because you see screws every day, every where, you may think they're not important or great. 因为你随时随地都能看到螺丝钉，就可能认为它们不重要或不伟大了。
But screws are very useful, important and great tools. 但螺丝钉是非常有用、重要且伟大的工具。
Screws look like nails, but they have spiral 1 shapes on their sides unlike nails. 螺丝钉看起来像钉子，但和钉子不同，它们的侧面有螺旋。
Therefore, instead of a hammer, a screwdriver 2 is necessary to use screws. 因此，使用它时不用锤子，而用螺丝刀。
Screws are very useful to fasten parts of a machine. 螺丝钉对于固定机器零件非常有用。
Almost every machine uses screws. 几乎每台机器都用到螺丝钉。
People have used screws for a really long time. 人们使用螺丝钉很长时间了。
Greeks and Romans used wooden screws about 2,500 years ago. 希腊人和罗马人从大约2500年前就开始使用木制螺丝钉了。
Now, people use various materials to make screws. 现在，人们使用各种材料来制造螺丝钉。
Stainless 3 steel is the most common material. 不锈钢是最常见的材料。
Plastic screws are also used for kids' toys. 塑料螺丝钉也用于儿童玩具。
adj.螺旋的；n.螺旋（线）；vi.盘旋上升（或下降）
- The production in this factory is spiral.这个厂的产量呈盘旋上升。
- Their profits began to spiral down disastrously.他们的利润开始螺旋形地急剧下降。
n.螺丝起子；伏特加橙汁鸡尾酒
- He took a screwdriver and teased out the remaining screws.他拿出螺丝刀把其余的螺丝卸了下来。
- The electric drill can also be used as a screwdriver.这把电钻也可用作螺丝刀。
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小学英语