第一段arge stretches of salmon habitat have been eliminated by human activity: .........The 【numerical effect】 is obvious: there are 【fewer】 salmon in degraded regions than in pristine ones
细节题,“ since the process provides a source of novel genes and a mechanism by which a location can be repopulates should the fish there disappear ” 的rephrase
should the stream recover=if the stream should recover虚拟语气
Clearly, using this test, doctors can largely avoid unnecessary removals of the appendix without, however, performing any fewer necessary ones than before, since ______.意思是:用这个检测,医生能够大量的避免对appendix不必要的移除,然而却不会比之前减少任何必要的移除。
因此,误诊的2%是增加unnecessary removal,而不是减少necessary removal。
这题妙啊!C