MTP-3中的DPC可能的来源是()和().
参考答案:由话务路由上定义、由SCCP的GT分析获得
It’s ________ hard for us ________ understand what he said.
A.to; too
B.too; to
C.to; to
D.too; too
怎么样划分新密咒和旧密咒?