There are 4 rows of saplings, 28 in each row. 38 trees have been watered. How many trees are left without watering?
有4行树苗，每行28棵．已经浇了38棵．剩下多少棵没有浇？
<gadget id="calculator">28 * 4</gadget>
<output>112</output>

<gadget id="calculator">112 - 38</gadget>
<output>74</output>

<result>74</result>