instrument lubricant

例句：

1. 1.The scientist used a microscope to examine the sample.
   科学家用显微镜检查样本。
2. 2. He played the piano as an instrument for entertainment.
   他弹奏钢琴作为娱乐的工具。
3. 3. The teacher used a ruler as an instrument to measure the length of the rod.
   老师用尺子作为测量工具来测量杆的长度。