Without good instructions of the teacher, you will be likely to___________ a lot of bad habits while you are practising the piano.

A．pull up

B．take up

C．pick up

D．bring up

杆上低压电气设备低压部分的交接试验分为线路和装置两个单元，线路仅测量绝缘电阻，装置既要测量绝缘电阻又要做工频耐压试验。测量和试验的目的，是对出厂试验的复核，以使通电前对供电的安全性和可靠性做出判断。( )