trebling

Their profits have trebled in the last two years.

最近两年他们利了三倍。

After uncovering of treble part we see valves underlaid by felt.

在揭露高音部分以后我们看见毛毡支持阀门。

They exist in four sizes: treble, tenor, bass, and double bass (violone).

高音、次中音、低音和双低音（低音提琴）。

His salary is treble mine.

他工是我三倍。

Patricia metham, the headmistress, said the number of applicants from mainland China had trebled in the past three years.

该校女校长帕特里夏·梅塔姆说，从中国大陆来申请人数量过去3年已经翻了三番。

It's value has trebled.

值已长到原来三倍。