For a vegetable field, use (2/9) of it to grow cabbage and (5/9) to grow cauliflower, what fraction of this vegetable field is left?
一块菜地，用它的(2/9)种白菜，用它的(5/9)种花菜，还剩这块菜地的几分几之？
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">1 - (2/9) - (5/9)</gadget>
<output>2/9 = around 0.222222</output>

<result>2/9 = around 0.222222</result>