If 2X-1=3, then 4X+2=how much.
如果2X-1=3，那么4X+2=多少．
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<result>10</result>