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Many people enjoy skiing, but more and more people are trying snowboarding（滑雪板运动）. No one is sure who started snowboarding. Many people think it was Jack Burchett. In 1929, Burchett made a simple snowboard out of wood and tied it to his feet.
Snowboarding is now a popular winter sport, but twenty years ago, snowboarders could not do it in ski resorts（滑雪胜地） because resorts’ owners thought it was a dangerous activity. Snowboarders usually found other places to enjoy the sport. Today snow boarders are welcome in most ski resorts. Snowboarding has become an Olympic sport.
Snowboarding is an exciting sport, but it can also be dangerous. Many snowboarders get hurt every year. Before snowboarding, you should take lessons and make sure you are in good health. You should also check your snowboard to make sure nothing is wrong with it. Remember, never snowboard alone.
An exciting winter sport | |
How it started | |
| People thought it was a |
Now | This winter sport becomes |
What to do before snowboarding | Take |
同类型试题
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x， x∈R， y∈[–1，1]，周期为2π，函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x， x∈[–1，1]， y∈[–π/2，π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
