If the length of the rectangle is increased by 2 cm and the width is also increased by 2 cm, what is the increase in the perimeter of the rectangle?
长方形的长增加2厘米，宽也增加2厘米，它的周长增加多少厘米
<gadget id="calculator">2 + 2</gadget>
<output>4</output>

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

<result>8</result>