橡皮擦，怎么擦掉铅笔字？

Pencil writing is made of tiny graphite bits. 铅笔字是细细的石墨粉。 Graphite is black and slippery. 石墨黑黑的、滑滑的。 The eraser is sticky and soft. 橡皮黏黏的、软软的。 Rubbing pushes the graphite toward the eraser. 一擦，石墨粉就被带向橡皮。 The rubber grips and curls the graphite up. 橡皮把石墨卷起来粘走。 The paper stays clean and the mark is gone. 纸面干净了，字也没了。