一个长方形的长是5米，宽是4米，它的周长是□米。□内应是[ ]
A． 5×4
B． 5+4
C．（5+4）×2
答案：C
The boy was doing homework while his mother dinner.
A．cooks
B．cooked
C．was cooking
D．will cook
徐州博物馆是一座现代化的地方综合性博物馆，开展业务有哪些？
