the development of a new jumbo rocket that is expected to carry the United State into its next phase of space exploration will be able to deliver a heavier load of insruments into orbit than the space shuffle and at a lower cost.D> a newly developed jumbo rocket, which is expected to carry teh United States into its next phase of space exploration, will be able to deliver a heavier load of instruments into orbit than the space shuttle can. and at a lower cost.
E> a newly developed jumbo rocket, which is expected to carry teh United States into its next phase of space exploration, will be able to deliver a heavier load of instruments into orbit than the space shuttle can. and to cost less.
这个题目我最后徘徊在DE之间 不知道该选择哪一个。我最后选择的E，这个题目的主干结构为……rocket will be able to ……， and …… 所以我认为句尾的and 应该与be able to 后面的部分并列，但是答案是D，很不理解。 请NN帮忙！！谢谢！！
-- by 会员 zoemiaoer (2010/2/3 6:04:52)