第14题: [单项选择]She began to be worried lest he ______ with some accident. A. had met B. should have met C. would meet D. met 参考答案:B 答案解析:在以lest和for fear that引导的状语从句中,谓语动词多用虚拟语气:通常以should+动词原形来构成。如:He took his raincoat with him for fear t
第25题: [多项选择]工业机器人安装在末端执行器上的夹持器分为( )。 A. 机械夹紧 B. 液压胀紧 C. 化学能吸附 D. 磁力夹紧 E. 真空抽吸 参考答案:A,B,D,E 答案解析:末端执行器又称手部,是操作机制性操作的装置。其上可按照夹持器、工具、传感器等。其中,夹持器可为机械夹紧、磁力夹紧、液压胀紧和真空抽吸四种。