1.The retired man donated most of his savings to the school damaged by the earthquake in Yushu ,________the students to

问题描述:

1.The retired man donated most of his savings to the school damaged by the earthquake in Yushu ,________the students to return to their classrooms.
A.enabling B.having enabled C.to enable D.to have enabled
选A.
2.Schools across China are expected to hire 50,000 college graduates this year as short-term teachers,almost three times the number hired last year,____ reduce unemployment pressures.
A.help B.to have helped C.to help D.having helped
选C.
两题都是高考题,为什么第一题不能用to enable?讲解说逗号后面不用不定式,可第二题是江苏09的高考题啊.who can tell me why?

第二题中的两个逗号中间部分是补充解释的,可以省去不看,后面部分和前面是不定式的关系