Thumb drives, external disc drives, and SD cards all show up right in the Files app.

拇指驱动器，外部磁盘驱动器，和SD卡都出现在文件应用程序中。

The problem is the disc drive is broken, so sometimes if you put a DVD into the disc drive it doesn't work.

光驱坏了，有时放入DVD光盘以后，光驱没有反应。