2-meter-long rope, cut off (1/2) for the first time, and cut off (1/2) meter for the second time, how many meters are left.
一根2米长的绳子，第一次剪去(1/2)，第二次剪去(1/2)米，剩下多少米．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 * (1/2)</gadget>
<output>1</output>

<gadget id="calculator">2 - 1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>