英语翻译

问题描述:

英语翻译
It has a long body.It has black heart.It walks on paper.It becomes shorter and shorter.what's it.
It is clean when it is black.It is dirty when it is white.what"s it.

这样东西很长,内芯是黑的,可以在纸上走.慢慢地,它就变短了.(铅笔pencil)
一样东西,它干净的时候是黑的,脏了就变白了.(黑板blackboard)