"Something else, which we hope does not happen very often, but which happens from time to time are the accidents which can release huge amounts of chemicals or radioactive-during Chernobyl, the radioactive things.

VOA: standard.2009.03.23

But people died typically of either infectious diseases or they died during childbirth, or they might have died at old age which would have been 50 or so at that time.

那时的人要么死于传染病,要么在分娩的过程中死去,或者在他们大约五十岁左右的时候,死于衰老

耶鲁公开课 - 生物医学工程探索课程节选

But people died typically of either infectious diseases or they died during childbirth, or they might have died at old age which would have been 50 or so at that time.

那时的人要么死于传染病,要么在分娩的过程中死去,或者在他们大约五十岁左右的时候,死于衰老

耶鲁公开课 - 生物医学工程探索课程节选