Xiaohua read (2/3) of a book, but did not read the whole book ((())/(())).
小华看了一本书的(2/3)，还剩全书的((())/(()))没看．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>