We've reconverted our high schools to be college preparatory.

我们已经将我们的高中改造成大学预科学校。

Simply put, bicarbonate is reconverted into carbon dioxide and then exhaled.

简单地说，碳酸氢盐再转化成二氧化碳，然后呼出。

Therefore, the bicarbonate is reconverted into carbon dioxide and subsequently expired.

因此，碳酸氢盐被重新转化为二氧化碳并随后排出。