A.电熨斗
B.微波炉
C.电饭锅
D.电烤箱
答案:B
If we don’t save energy, it _____ some day.
A.will be run out
B.has been run out
C.will run out
D.has run out
计算:5(a2b-3ab2)-2(2a2b-7ab2)