A:What a pity!
B:Doesn’t matter.
C:How come?
D:What has become of him?
“小时候,妈妈为我洗脚;长大后,我为妈妈洗脚。”从法律角度看,这句公益广告词体现了( )
廖智老师的感人事迹对我们有什么启示?