新中国成立后，我国的高等教育目的经历了从培养“劳动者”、培养“人才”、培养“建设者和接班人”、培养“公民”的转变过程。
参考答案：对
—Have you been teaching here since graduation?
—No, I _____ on a farm for five years．
A．had worked
B．have worked
C．was working
D．worked
在RS-232C标准中，规定发送电路和接收电路采用( )接收。
A．单端驱动双端
B．单端驱动单端
C．双端驱动单端
D．双端驱动双端
