Depression, unexplained fear and unreasonable actions are the_______of a patient with mental health problems.
A.marks
B.systems
C.symbols
D.symptoms
如果一个二极管正、反向电阻值都很大,则二极管()状态。
如果一个二极管正、反向电阻值都很小,则二极管()状态。
I guess Professor Wang hasn’tfinished grading the papers yet. If he had, he would not keep us in_______ .
A.suspense
B.trouble
C.doubt
D.wonder