问题
选择题
关于力的作用效果，下列说法正确的是[ ]
A、物体运动状态改变了，一定是受到了力的作用
B、物体受到了力的作用，运动状态一定改变
C、物体受到了力的作用，形状一定改变
D、以上说法皆不正确
答案
答案：A
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关于力的作用效果，下列说法正确的是[ ]
A、物体运动状态改变了，一定是受到了力的作用
B、物体受到了力的作用，运动状态一定改变
C、物体受到了力的作用，形状一定改变
D、以上说法皆不正确
答案：A
| 完形填空。 | ||||
| Have you ever seen a rainbow (彩虹) in the sky? Do you know what it is? A story says that when you see a rainbow you should 1 at once to the place where it touches (触摸) the ground, and 2 you would find a bag of gold. Of course, it is not 3 . You could not find the bag of gold, nor could you ever find its end. No matter how 4 you run, it always seems far away. A rainbow is not a thing which we can feel with our 5 as we can feel a flower. It is only the effect (效果) of light shining on raindrops (雨滴). The raindrops catch the sunlight and break it up into all the wonderful colors which we see. It is 6 a rainbow perhaps because it is made up of raindrops and looks like a bow (弓). That is 7 we can never see a rainbow in a clear 8 . We see rainbows 9 when there is rain in the air and the sun is shining brightly through the clouds. Every rainbow has many colors in the same order. The first of the top color is always red, next 10 orange, then green, and last of all blue. A rainbow is indeed one of the wonders of nature. | ||||
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