I go to bed at 9 o'clock every night and wake up at 6 o'clock in the morning. How many hours have I slept in total?
我每天晚上9时睡觉，早上6时起床，一共睡了多少小时．
<gadget id="calculator">12 - 9</gadget>
<output>3</output>

<gadget id="calculator">3 + 6</gadget>
<output>9</output>

<result>9</result>