✔ 最佳答案
雖然已有很多人給予答案,但也想在這裏與大家交流一下
首先helped絕對不是原形動詞
發問者之所以覺得問題中的必是原形動詞,是因為很多的問句是以以下的形式發問:
What do you want?
How much did you pay?
How much does the room cost?
What did she want?
這種問句的形式是 :疑問詞+助動詞+主詞+原形動詞
但當疑問詞是主語是,一般就不能用do或did
如:
Who said that? (who是主語)
請留意
Who did you invite?(who是賓語,所以用did)
就因為Who helped the lady?的who是主語,故不能寫成Who did help the lady?
因此不能用上did,此時,要表達時間性,就得以在主動詞help裏表達
希望幫到你!