"doubling with a computer took no time at all"
"I decided his double was a bluff"
The rapid doubling of the population.
出自: R. W. Emerson
Intourist had given some of our booked rooms to a delegation from Mongolia, which meant a lot of doubling up.
出自: A. Garve
A violinist anxious to learn a 'doubling instrument'.
出自:Melody Maker