life什么情况下用复数
life
n.生命;人命;性命;人的存活;生物;活物；
复数 lives；
例句
The cost in terms of human life was high.
付出了很大的生命代价。
People tend to work hard at this stage of life.
人在这个人生阶段往往发奋努力。
The operation could prolong his life by two or three years.
这次手术可使他多活两三年。
They had got too used to the soft life at home.
他们实在是过惯了家里的安逸生活。