Xiaohua wrote 257 words yesterday, and today he wrote twice as many words as yesterday. How many words did he write in two days?
小华昨天写了257个字，今天写的字是昨天的2倍，他两天一共写了多少个字？
<gadget id="calculator">257 * 2</gadget>
<output>514</output>

<gadget id="calculator">257 + 514</gadget>
<output>771</output>

<result>771</result>