钢水中的磷是一种有害元素，它可使钢产生（）。
参考答案：冷脆
气虚型经行感冒最佳选方为（）
A.补中益气汤
B.屏风散
C.防风通圣散
D.归脾汤
E.桂枝汤
Electronic computers (), the complicated mathematical operations, such as weather forecast and the control of satellites, can be done quickly and accurately.
A. being used
B. used
C. having been used
D. to be used
