13.(By law,a qualified physician can only prescribe medicine, protecting the public). A)By law,a qualified physician can only prescribe medicine, protecting the public D)In order to protect the public,by law a qualified physician only can prescribe medicine. E)In order to protect the public,by law only a qualified physician can prescribe medicine. 答案是E,但是这里的only完全变了位置,修饰的重点变了,逻辑意思也完全不同了。而且,如果可以变换的话,D为什么不对? 18)Interest rates on mortgages (have declined steadily during the first six months of this year but virtually remained unchanged) during the next three months. A)have declined steadily during the first six months of this year but virtually remained unchanged. E)declined steadily during the first six months of this year but have virtually remained unchanged 答案是E A)中后半部分remained不能看做是have remainedd的省略形式么?前面用“现在完成时”不对么? E)中后半部分的“现在完成时”的依据是那个时间状语么? 晕! 哪位牛牛指教一下!