——It’s generous Millie to donate all her pocket money to UNICEF．
——Yes．It is really meaningful us to do something for charities．
A. of；of
B. for；for
C. for；of
D. of；for
网友回答
A. of；of
B. for；for
C. for；of
(答案→)D. of；for
解析：“It is + adj.+ of sb.+ to do sth”句型中的adj.跟sb.有关,这个adj.是用来形容sb.的,表示某人这么做真是太adj.了，故第一空用of；而“It is + adj.+ for sb.+ to do sth”表示做某事对某人来说很adj.，这里的adj.是do sth的属性，里面的sb.跟adj.没有直接联系，故第二空用for。故根据句意选D。