tripling

The tripling of the city's population in ten years created a housing shortage.

用法提示：tripling 作名词，表示“增至三倍”这件事。

We were not prepared for the sudden tripling of our electricity bill.

用法提示：tripling 作名词，与 the sudden 连用，指费用突然增至三倍。

The company announced the tripling of its production capacity next year.

用法提示：tripling 作名词，在 the tripling of 结构中表示“增至三倍”。