Dad bought back 3,000 grams of soybean oil. After eating 1,000 grams, he bought back 2,000 grams of vegetable oil. How many kilograms of oil is left?
爸爸买回3000克豆油，吃掉1000克后，又买回2000克菜油，还有油多少千克？
<gadget id="calculator">3_000 - 1_000</gadget>
<output>2_000</output>

<gadget id="calculator">2_000 + 2_000</gadget>
<output>4_000</output>

<result>4_000</result>