因此在第二秒内，速度没变。

So during the second second, the velocity is not changing.

youdao

在第二秒，从+ 3移动到，又移动了6米。

Then in the second second -3 it goes from plus three to minus three so it travels another six meters.

youdao

录制音频的第一第二秒可能非常响亮。

First second of recorded audio may be very loud.

youdao

That is, it doesn't take one second to go the first, and then two seconds to go to the second, and three seconds to go to third.

就是说,不是第一秒到第一排,第二秒第二排,第三秒第三排这样

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