dien

例句：

1. 1.天，天空；2. 时间；3.
   用于表示“在...之内”或“在...期间”
2. 1. The sun is shining brightly today.
   今天太阳灿烂地照耀着。
3. 2. Time flies when you're having fun.
   当你玩得开心时，时间飞逝。
4. 3. During the summer vacation, I spent most of my days reading books.
   暑假期间，我大部分时间都在阅读书籍。