修一条长1500米的路，已经修了3天，还剩600米，平均每天修多少米？
（1500-600）÷3，
=900÷3，
=300（米）；
答：平均每天修300米．
27．After the adventure, the children returned home, ______.
A．safe but tired
B．safely but tiredly
C．safely but tired
D．safe but tiredly
黄巾起义有何特点？
