工作人员具备必要的电气知识和（），熟悉电气设备及其系统。
A.操作技能
B.业务技能
C.技能
D.技术
参考答案：B
阅读小天地。根据短文内容判断下列句子的正(√)误(×)。
December 25th is Christmas Day. It is an important (重要的) holiday in the West. During (在……期间)
Christmas Day, people don't work, children don't go to school. Most families get together and have a big dinner.
They give and receive gifts and visit friends. The Christmas tree is an important part of Christmas. Most families
buy a tree. They also buy many things to put up the tree.
( ) 1. November 25th is Christmas Day.
( ) 2. Christmas is an important holiday in China.
( ) 3. In the west, people don't work, children don't go to school on Christmas day.
( ) 4. In the west, most families get together and have a big dinner on Christmas day.
( ) 5. The Christmas tree is an important part of Christmas.
固定桥的稳定是指（）
A.口腔行使各种功能运动时，基牙及支持组织不发生下沉、松动、移位等
B.基牙牙冠形态正常，龈高度足够，轴壁聚合度较小，具备良好的固位形
C.固位体具备足够的摩擦力、粘结力和约束力
D.口腔行使各种功能运动时，能够抵抗外力，不致松动或脱落，固位体牢固地固定在基牙上
E.在口腔行使各种功能运动中受到各个方向外力时，能够保持固定桥的平衡而不会出现翘动
高度足够，轴壁聚合度较小，具备良好的固位形