一般过去式不规则动词：buy—bought, come—came — 英语选择题
题目
At a school fair, Ben came early. He bought a storybook before his friends came. Which sentence is correct? A. Ben come early and buy a storybook. B. Ben came early and bought a storybook. C. Ben came early and buy a storybook. D. Ben come early and bought a storybook.