If the length of a rectangle is increased by 4 cm and the width remains the same, what is its perimeter and the perimeter of the original rectangle?
一个长方形的长增加4厘米，宽不变，它的周长和原来长方形的周长多少
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<result>8</result>