A piece of cloth is 2 meters long, and (2/3) meters are used up. How much rice is left?
一块布长2米，用去(2/3)米．还剩多少米？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">2 - (2/3)</gadget>
<output>4/3 = around 1.333333</output>

<result>4/3 = around 1.333333</result>