A rectangular frame with a length of 12 cm and a width of 7 cm is nailed with thin wooden strips. If it is drawn into a parallelogram, what is its perimeter in cm?
用细木条钉成一个长方形框，长12厘米，宽7厘米，如果把它拉成一个平行四边形，它的周长是多少厘米．
<gadget id="calculator">12 + 7</gadget>
<output>19</output>

<gadget id="calculator">19 * 2</gadget>
<output>38</output>

<result>38</result>