Question

8．这种方法能用来预防感冒．
This method can be used to guard against catching a cold．

Answer 1

分析 This method can be used to guard  against catching a cold．

解答 答案：This method can be used to guard against catching a cold．这里是说客观事实用一般现在时，主语the method这个方法，是动词use的承受者，构成被动关系，情态动词can能，故用情态动词的被动语态---情态动词+be+过去分词，use sth to do sth用某物做某事，被动语态是be used to do sth，故This method can be used to，预防…guard against，后加名词代词或动名词，catch a cold感冒，catch的动名词catching，故答案是This method can be used to guard against catching a cold．

点评 used to do 过去常常做某事 
be used to doing 习惯于做某事 be used to do sth被用来做某事