If it takes 4 minutes to saw a piece of wood into 2 pieces, how many minutes will it take to saw this piece of wood into 4 pieces?
把一根木料锯成2段需要4分钟，要把这根木料锯成4段，需要多少分钟．
<gadget id="calculator">2 - 1</gadget>
<output>1</output>

<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<result>12</result>