Wrong 4x-8 as 4(x-8), the result is much less than the original
把4x-8错写成4(x-8)，结果比原来少多少
<gadget id="calculator">4 * 8</gadget>
<output>32</output>

<gadget id="calculator">32 - 8</gadget>
<output>24</output>

<result>24</result>