For many such purposes gangs of captives were cheaper and far more controllable than levies of the king's own people. 赫伯特·乔治·威尔斯.世界史纲.
But the little battery with its metal plates in a weak solution proved a perennial reservoir of electrical energy, safe and controllable, from which supplies could be drawn at will. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
He kissed her cheek, and departed in great misery, which was several hours in lessening itself to a controllable level. 托马斯·哈代.还乡.