4-(4/5)/4-(4/5).
4-(4/5)/4-(4/5)．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) / 4</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">4 - (1/5) - (4/5)</gadget>
<output>3</output>

<result>3</result>