Hurry up! The train_____in two minutes. [ ]
A.will go
B.go
C.goes
D.went
答案：A
行×列表的自由度是（）
A.行数-1
B.列数-1
C.行数×列数
D.（行数-1）×（列数-1）
E.样本含量-1
--Have you finished your work yet?
--Yes, I have . It ____________ half an hour ago.
A．has been finished
B．finished
C．was finished
D．has finished
