一般是 有be动词和情态动词的 就把be动词和情态动词前置 如 He is a boss.Is he a boss?They can swim.Can they swim?如果句子中 没有be动词和情态动词 就要引进 助动词 do 助动词do要根据人称和时态的变化而变化 如 He likes music.Does he like music?We went to the park yesterday.Did you go to the park yesterday?大抵如此了 多观察正确答案 考虑为何那样变化 你就会熟悉了 也就运用自如了 Good luck 2 U !