速度变动率越大,调节系统的静态特牲线越陡。因此,调频机组的速度变动率应大些。
参考答案:错
I heard that you really had a wonderful time at John's birthday party, _____?
A.didn't I
B.didn't you
C.hadn't you
D.will you
以下足癣类型中,四季皆可发生,以冬季多见或加重的是( )
A.间擦型
B.水疱型
C.鳞屑型
D.角化型
E.体癣型