文件夹特性

例句：

1. 1. She keeps all her important documents in a folder on her desk.
   她把她所有的重要文件都放在她的桌子上的一个文件夹里。
2. 2. The teacher asked the students to put their folders in the bin.
   老师要求学生们把他们的文件夹放到垃圾桶里。
3. 3. He carefully opened his folder and took out the papers he needed.
   他小心翼翼地打开了他的文件夹，拿出了他需要的文件。