expounder

例句：

1. 1.The professor is an excellent expounder of complex theories.
   这位教授是复杂理论的杰出阐释者。
2. 2.She is a great expounder of history for children.
   她为孩子们讲述历史时讲得非常好。
3. 3. The lecturer was an expounder of the new policy.
   这位演讲者是新政策的阐释者。