揭阳实验小学八月份用水160吨，比七月份节约用水40吨，节约用水百分之几？
40÷（160+40），
=40÷200，
=20%；
答：节约用水20%．
____, I had to buy a new one.
A．My dictionary losing
B．My dictionary having been lost
C．Because my dictionary lost
D．My dictionary had been lost
侵犯皮肤表面的接触性急性化脓性感染是
A．痈B．疖C．蜂窝织炎D．丹毒E．脓疱疮
