medium heavy-duty class

例句：

1. 1. Thetemperature is medium for this region.
   这个地区的温度适中。
2. 2. The company uses a medium tocommunicate with its employees.
   该公司使用一种媒介与员工沟通。
3. 3. The book is a mediumof communication between the two cultures.
   这本书是两种文化之间的交流媒介。