雅思考官录口语机经  RA 7

雅思考官录口语机经 RA 7

2017-10-08    00'33''

主播: 海外东方学院

620 49

介绍:
Academic authors could do a better job of helping journalists, but often they have presented their work for fellow experts, without signposts for lay readers. And, just as often, reporters demand a certainty about cancer that scientist cannot give. Because it is impossible to prove a negative, prudent doctor and researchers can never say for certain that something does not cause cancer. All they can say is that given the evidence, it is extremely unlikely.