谦虚____(骄傲;谨慎)
善良____(友善;凶恶)
幸福____(痛苦;烦恼)
清澈____(清亮;浑浊)
计算:
(1)2y2x32--x2y3
(2)x2-2x+1x2-1÷x-1x2+x
I'd like __________ and __________.