But I was eight years old and I was terrified. I think it took me like two months to go off it with the full speed and actually go anywhere,"

VOA: standard.2010.01.31

One way is to say, if I do a full revolution, I think of the speed as a distance over time.

一种方法是,如果我转完整的一圈,我认为速度就是距离除以时间

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