The problem concerns the average lifespan of civilization advanced enough to be capable of such communication . 问题在于延长文明的平均寿命，才能适应这样的通信。
The heavy wear on engines in their flight over vast barren sandy spaces reduced their flighting life . 在飞越荒芜的大片沙漠时，引擎的耗损很大，因而缩短了它们的飞行寿命。
A mean strain or prestrain, as in fig. 83, can under certain conditions reduce the subsequent fatigue life . 一个如图83所示的平均应变或预应变，在某种情况下，能够缩短以后的疲劳寿命。
Weak and sick, perpetually coughing, zire buzette, who had not long to live, had nevertheless already buried two wives . 体弱多病，老是咳嗽，寿命不长的齐雷比泽特，竟然先后送了两个老婆入土。
Some authors have even supposed that, as the individual has a definite length of life, so have species a definite duration . 有的作者甚至假想，个体既有一定的寿命，物种的存续也当有一定的期限。
A bulb at the connector end provides a reservoir of filling gas which is necessary to give a reasonable working life . 在连接体的末端有一个小球，用以贮存所充的气体，其目的是为了使计数器具有适当的工作寿命。
Results of bearing-life tests with oil-impregnated retainers here been rather spotty; the lives range from only a few to over 10, 000 hours . 对油浸保持架轴承寿命试验的结果很不一致，从几小时到一万小时以上不等。
My average life is 18 months, during which i change from a crisp bill to a limp rag with broken edges and turned corners . 我的平均寿命是18个月，在此期间我从一张挺括的纸币变成一张软绵绵的边也坏了，角也折了的破票子。
A large manufacturer of windshield wiper blades needs to estimate the mean life users of the blades can expect under typical driving conditions . 一个大型挡风玻璃雨刷厂的经理，需要估计一下在一般驾驶条件下雨刷平均使用寿命的期望值有多大。
Before opec, the average life expectancy of cartels had been so short that the economic analysis of cartels tended to stress the inevitability of their collapse . 在石油输出国组织以前，卡特尔的平均期望寿命是如此之短，以致对卡特尔的经济分析往往是强调其解体的不可避免性。
