The old woman is _a_60 and 70 years old.
a.between   b.about   c.during   d.over
  2.They are as _c_ as usual.
       a.happily   b.busily   c.friendly   d.carefully
  3.Even on holidays Mr.Wang preferred _c_ to __ nothing.
       a.read;do   b.to read;do   c.reading;doing   d.to reai;doing
 
我把答案都写在下划线上了,可是不知道为什么选这个选项,望有老师能简单说一下每题答案的原因~