Obtaining an investment-grade rating will keep the county's future borrowing costs low, protect its already-tattered image, and increase its ability to buy bond insurance. (A) Obtaining an investment-grade rating will keep the county's future borrowing costs low, protect (B) To obtain an investment-grade rating will keep the county's future borrowing costs low, and protect (C) Having obtained an investment-grade rating will, in keeping the county's future borrowing costs low, protect (D) To obtain an investment-grade rating would keep the county's future borrowing costs low, protecting (E) Obtaining an investment-grade rating, keeping the county's borrowing costs low, would be protecting 答案没有问题。想问一个题外话:前面是county's,后面用its可以吗? 都说A'B中A不能被指代,是不是its算另外一种形式,不适用这个规律呢? 因为5个答案都是这样,所以在做题时就只能忽略了。 但是还不放心,请教NN |