tgn

例句：

1. 1.I've never heard of this tgn before.
   我以前从未听说过这个tgn。
2. 2.The tgn is a secret that only a few people know.
   这个tgn是一个只有少数人知道的秘密。
3. 3. The tgn has been the subject of much debate in recent years.
   这个tgn在过去几年里一直是争论的焦点。