金属在外力作用下变形,外力除去后能恢复到原来的形状是()。
A.弹性变形
B.塑性变形
C.永久变形
参考答案:A
In order to continue to learn by ourselves when we have left school, we must ______ learn how to study in the school now.
A.in all
B.after all
C.above all
D.at all
下列哪些地方曾遭受到DDoS攻击()
A.江苏
B.爱沙尼亚
C.潍坊
D.济南