A rectangular lawn is 4 meters long and 3 meters wide, what is the perimeter of the lawn in meters?
一块长方形草坪长4米，宽3米，这块草坪的周长是多少米．
<gadget id="calculator">4 + 3</gadget>
<output>7</output>

<gadget id="calculator">7 * 2</gadget>
<output>14</output>

<result>14</result>