1. Similiar to central extension. Theconcepts of extended centroid extension is introduced, the primitivityof extended centroid extension on prime GPI-rings is studied. 类似于中心扩张，本文引入了广义形心扩张的概念，且研究了广义形心扩张的本原性。
2. Similiar to central extension. Theconcepts of extended centroid extension is introduced, the primitivityof extended centroid extension on prime GPI-rings is studied. 类似于中心扩张，本文引入了广义形心扩张的概念，且研究了广义形心扩张的本原性。
3. Smiling service. , reassured service and standard service, our commitment to the custom and the concrete embodiment of our sound service relationship. 微笑服务、放心服务、规范化服务、是我们对客户的承诺与我们良好的服务关系的具体体现。
4. Guiding Service quality depends on regular service as well as psychal service or emotional service . 导游服务质量不仅取决于常规性服务更取决于心理服务或情绪性服务。
5. With roaming password: PIN can be any extension expired, and by extension the level of restrictions. 具有密码漫游功能：用个人密码可以在任何分机呼出，且受该分机等级限制。
网络释义
extension telephone set telephone extension 电话分机;
extension telephone set telephone extension 电话分机;
The University of Michigan Digital Library eXtension Service 密西根大学数字图书馆推广服务;
