10. The widely accepted big bang theory holds that the universe began in an explosive instant ten to twenty billion years ago and has been expanding ever since. (A) that the universe began in an explosive instant ten to twenty billion years ago and has been expanding (B) that the universe had begun in an explosive instant ten to twenty billion years ago and had been expanding (C) that the beginning of the universe was an explosive instant ten to twenty billion years ago that has expanded (D) the beginning of the universe to have been an explosive instant ten to twenty billion years ago that is expanding (E) the universe to have begun in an explosive instant ten to twenty billion years ago and has been expanding A选项中and 前后的began与has been expanding形式并不一致,为什么A选项还是正确的 -- by 会员 STshadow (2012/9/10 16:48:20)
parallelism dictate verb parallel with verb ; the verb form(tense)are not required to be the same in every circumstances;you should use the context to determine |