twice /twais/ adv. 1.两次：She writes to her parents twice a month. 她一个月给父母写两次信。 2.两倍：Twice three is six. 3的两倍是6。［考句］Americans eat twice as much protein as they actually need every day. 美国人每天摄入的蛋白质是他们实际需要的两倍。