There are 46 willows and poplars, and 18 poplars. How many fewer poplars are there than willows?
柳树和杨树一共有46棵，杨树有18棵．杨树比柳树少多少棵？
<gadget id="calculator">46 - 18</gadget>
<output>28</output>

<gadget id="calculator">28 - 18</gadget>
<output>10</output>

<result>10</result>