【高中英语题】关于高中英语非谓语动词的用to do和doing的问题

【高中英语题】关于高中英语非谓语动词的用to do和doing的问题
我有两道错题.
The retired man donated most of his savings to the school damaged by the earthquake in Yushu,______the students to return to their classroom.
答案选的是enabling,我选的是to enable,不能把 to enable看做表示目的吗?
More highways have been built in China,______ it much easier for people to travel from one place to another.making,我选的to make.一样的理由,想看做表示目的.