a.

1. 严肃的；庄重的；庄严的
   He was very solemn and refrained from talking.

   他很严肃，沉默寡言。

2. 隆重的；郑重的
   He made a solemn promise to do better.

   他郑重保证要做得更好。

   The inauguration was a solemn event.

   就职典礼是一件隆重的大事。

3. 严重的，严正的
   The government made a solemn statement.

   政府发表了一项严正的声明。

4. 正式的；神圣的，宗教上的
   The President took the solemn oath of office.

   总统正式宣誓就职。

adj.

1. formal and dignified:
   a solemn procession.
2. not cheerful; serious.
3. deeply sincere.