lifepak手提式心脏除颤器(商品名)lifen.一生；生命；生活；人生life circle cost寿命周期费用Life Saving Ship救生船life composition生活作文life of teaching教学生活life orientation生活取向life threateningph.life lengthening寿命延长life-time test寿命测试life repair cost全使用期内修理费life of delivery交割生命周期