定位:1. /1981 discovery /of...
2. The vertebrate skeleton /had traditionally been regarded/ as a defensive development, ... that vertebrates /became predators/. The first vertebrates, ... would have been easy prey for numerous invertebrate carnivores, 一直虚拟语气,而第一段最后就提到了1981年的这个发现对于development of the vertebrate skeleton有重大意义,所以1981年发现与二段开头的观点相反,与However, other paleontologists 的观点一致,即第一批有脊动物是捕食者
OG解释A:The phrases the possibility...warmer and to what...might are not parallel.
B:The verb form has had as its focus is unnecessarily wordy; the noun clauses are parallel in form, but it is not clear what the extent refers to.
critique和vision都是”essay“的同位语
因此需保持平行关系 同为动词或同为名词
不是功能平行就可以吗,为什么要严格意义上的语法平行
envisioning是verb.+ing,不属于严格意义上的noun...相比较而言肯定是名词vision更好吧
明白明白
同学,你是最近在学Gmat吗?要不加个微信交流一下吧
yeile_ff