六级词汇笔记单选题词汇解析7

　　55.There is supposed to be a safety ___________ which makes it impossible for trains to collide.

　　A.appliance 机械 装置

　　B.accessory 附件 零件 配件

　　C.machine

　　D.mechanism

　　56.After four years in the same job his enthusiasm finally _______ .

　　A.deteriorated 恶化 变化=degenerate 变坏 堕落

　　B.dispersed 散开 消散

　　C.dissipated 消散 消失

　　D.drained 耗尽

　　解析：

　　finally 最终

　　dominish 消失减少 (同义：smother eliminate)

　　shrink 缩水