Tom: Thank you. Don’t trouble yourself. I’m not thirsty at all.
Henry: _________you wouldn’t like a cold beer, or a coke?
A.Can you tell
B.Are you sure
C.Do you think
D.Do you mean
Keith:__________,do you know where the police station is?
Woman:No,I‘m sorry,I don’t.I‘m not from around here.
A.I"m sorry
B.Excuse me
C.Pardon
D.Attention
A.当电源电压不变,负载变化时:n=f(I)
B.当电源电压不变,负载变化时:n=f(M)
C.当电源电压改变,负载不变时:M=f(n)
D.当电源电压改变,负载不变时:M=f(I)