A rope is 8 meters long, if 4 meters are cut off, what is cut off is the rest
一根绳子长8米，剪去4米，剪去的是剩下的多少
<gadget id="calculator">8 - 4</gadget>
<output>4</output>

<gadget id="calculator">4 / 4</gadget>
<output>1</output>

<result>1</result>