你注意观察过家里的自行车吗?下列关于自行车增大摩擦或减小摩擦的说法,哪个是错误的?( )
A:轮胎上刻有凸凹不平的花纹,是为了增大摩擦
B:刹车时用力捏闸是为了增大摩擦
C:往车轮轴承上加润滑油是为了减小摩擦
D:车轮上装有滚动轴承,是为了增大摩擦
—Yes, and most of them __in the western part of China.
The population of the world is ____ (increase) by 80 million every year.
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