laser lower level

例句：

1. 1.The laser is used for cutting metal.
   激光用于切割金属。
2. 2. The laser printer can printhigh-quality documents quickly.
   激光打印机可以快速打印高质量的文件。
3. 3. The laser beam wasdirected at the target.
   激光束被瞄准目标。