多址技术是指多个独立用户同时使用传输介质而互不影响。
参考答案:对
My mother ____________, " ____________ run and jump." [ ]
A. say; Do
B. says; don't
C. says; Don't
A.音调不变,响度变大
B.音调变高,响度变大
C.音调不变,响度变小
D.音调变低,响度变小