Although my brother couldn't speak French, he was top in his class at counting backward by threes.

虽然我哥哥不能讲法语，但他在他们班里一至三的倒数计算却名列第一。

youdao

She was looking out the window and counting - counting backward.

她望着窗外，在计数——倒数上来。

youdao

She was looking out the window and counting C counting backward.

VOA: special.2009.08.01