父母
両親の父母
the parents of one's parents
a parent of your grandparent
父母に仕える
父母の父親
a father of your grandparent
I have both parents living.
a mother of your grandparent
父母の兄
You should honour your parents.
one's great-great-grandparents in China, the founder of a dynasty
よく父母につかえる
of a relationship, a person who is a father to a grandparent
in place of the parents