______是电路中形成电流的原因，而______是提供电压的装置．
电压是电路中形成电流的原因，而电源是提供电压的装置．
故答案为：电压；电源．
—Everybody says you are a good student，you never fall asleep in class，do you？
—_____ ．
A．Yes，sometimes
B．No，I did
C．Yes，never
D．Yes，I didn't
There are many methods in the CPETT .One of them is the method that runs a Kernel as the load of a computer. So we call it
A．Monitor method
B．Model method
C．Benchmark method
D．Physical method
