甜菜制糖的主要区位条件是[ ]
A、原料产地
B、技术力量
C、市场
D、廉价劳动力
答案：A
—Don't ________ until you ________.
—OK.I'll remember that.[ ]
A. tell; are spoken to
B. speak; are spoken
C. say; are spoken
D. speak; are spoken to
从内存中清除内存变量的命令是________。
A．Release
B．Delete
C．Erase
D．Destroy
