1·The nation's infant mortality rate has reached a record low.
该国的婴儿死亡率已达历史最低。
—— 《柯林斯英汉双解大词典》
2·However, Zaire, with its 90% mortality rate, was even worse.
然而，扎伊尔的情况更糟，死亡率高达90%。
3·In the late 1970s, the infant mortality rate for the children of illiterate mothers was around 110 deaths per thousand live births.
在1970年代后期，在文盲母亲所生的孩子中，婴儿死亡率约为每1000名活胎婴儿中有110个夭折。
4·In the Amazon, my colleagues and I found the mortality rate for the biggest trees had tripled in small patches of rainforest surrounded by pasture land.
在亚马逊河流域，我和我的同事们发现，在被牧场包围的一小片雨林中，最大的树木的死亡率增加了两倍。
5·Since dolphins rid their bodies of the compounds rapidly once exposure ceases, their mortality rate should decline rapidly if such boat paints are banned.
由于海豚一旦停止接触，它们会迅速地将身体里的化合物清除，所以如果禁止使用这种船用油漆，它们的死亡率就会迅速下降。