So, it was a win-win situation _______was why we did not hesitate _______ with them.
A:where, to partner
B:which, to partner
C:where, partnering
D:which, partnering
—I don't like to use QQ to communicate with my classmates. What about you, Maria?
—I don't, _______.
把方程x2+6x+3=0变形为(x+h)2=k的形式,其中h,k为常数,则k=____