There were 9 books just now, Dad bought him 5 more, Xiao Ming borrowed 2 more, how many books are there just now?
刚刚有9本书，爸爸又给他买了5本，小明借去2本，刚刚还有几本书？
<gadget id="calculator">5 - 2</gadget>
<output>3</output>

<gadget id="calculator">9 + 3</gadget>
<output>12</output>

<result>12</result>