white slate pencil

例句：

1. 1.This white slate pencil is very sharp and easy to use.
   这支白石铅笔非常锋利且易于使用。
2. 2. She used a white slate pencil to draw the picture on the whiteboard.
   她用一支白石铅笔在白板上画了这幅画。
3. 3. The teacher asked the students to write their homework on the white slate pencil.
   老师要求学生们用白石铅笔写作业。