Not "I didn't went." — say "I didn't go.". 过去的意思已经在 didn't 里了，所以动词还原成原形：go，不是 went。
试一试: Mei: Where was Yasmin last night? Liam: Her train didn't come. She ___ to the party. 补全 Liam 说的话。 (didn't go / didn't went / didn't goed) 答案: didn't go — didn't 后面动词还原成原形：didn't go。"went" 和 "goed" 都是想再表示一次过去，但 didn't 已经做到了。
Did + 动词原形（提问）
要问过去的事，把 Did 放在句子最前面，再用动词原形。道理一样：Did 已经带着过去的意思，所以动词保持原形。
She worked here. → Did she work here?
You went out. → Did you go out?
They saw you. → Did they see you?
Not "Did you went out?" — say "Did you go out?". Did 已经表示过去了，所以动词还原成原形：go，不是 went。
试一试: Mei went to the party. 问 Mei 是否去了聚会。 答案: Did Mei go to the party? — 先说 Did，再说主语，最后是动词原形：Did Mei go to the party? "went" 不要放进去。Did 已经带着过去的意思，所以动词还原成 go。
试一试: Lars saw the email. 问 Lars 是否看了那封邮件。 答案: Did Lars see the email? — 先是 Did，再是 Lars，最后是动词原形：Did Lars see the email? "saw" 不要放进去。过去的意思已经在 Did 里了，所以动词是 see。
简短回答：Yes, I did
回答 Did 提出的问题，单独用 did 就行，不用主要动词：Yes, I did. / No, I didn't.
Did you go? → Yes, I did.
Did she call? → No, she didn't.
Did they win? → Yes, they did.
Not "Did you go? → Yes, I do." — say "Did you go? → Yes, I did.". 回答时用问题里的那个词：Did 问的是过去，所以回答用 did，不是 do。
试一试: Did Mei enjoy the trip? → Yes, she ___. (did / does / enjoyed) 答案: did — 问题里用了 Did（过去式），回答也要对应：Yes, she did（不是 "does"，也不是主要动词）。
Did / didn't 后面用动词原形
在 Did 或 didn't 后面，动词永远用原形。过去的意思已经在 did 里了，所以不用再表示一次。
Did you see it? (not "Did you saw it?")
She didn't go. (not "didn't went")
Did they eat? (not "Did they ate?")
试一试: ___ you like the movie last night? (Did / Do / Was) 答案: Did — "Last night" 是过去，所以用 Did 开头。"Do" 问的是现在，"Was" 不放在 "like" 这样的动作词前面。
过去的意思去哪儿了？
看过去的意思落在哪里。He went. 里它在动词上。He didn't go. 和 Did he go? 里它在 did 上，所以动词变回原形。
He went home. → He didn't go home.
She saw it. → Did she see it?
They ate. → They didn't eat.
试一试: Hiroshi: Amina didn't come to class. Mei: I know. She is sick. She ___ home early yesterday. 补全 Mei 说的话。 (went / didn't went / goes) 答案: went — Mei 没有用 did，所以过去的意思就放在动词本身：went。有一个选项把过去的意思放了两次，另一个说的是 Amina 平常做的事——可 yesterday 已经过去了。
试一试: Camila: Why is the window open? Yasmin: Lars didn't ___ it. 补全 Yasmin 说的话。 (close / closed / closes) 答案: close — Didn't 已经带着过去的意思，所以后面的动词保持原形。有一个选项在动词上又加了过去，另一个是现在时里跟 he、she、it 搭配的形式。
Where did you go?
先说疑问词，再说 did，然后是人，最后是动词原形：Where did you go?
You went to the park. → Where did you go?
She bought a shirt. → Where did she buy it?
They met at the library. → Where did they meet?
试一试: Lars: ___ did you go after class? Lani: To the cafe on Moffen Street. 补全 Lars 的问题。 (Where / What / When) 答案: Where — Lani 回答的是一个“地点”，所以 Lars 问的一定是地点。另外两个，一个问东西，一个问时间，都对不上她的回答。
What did you do?
What did you do? 问的是整件事做了什么。回答是一个过去时的句子：I met a friend.
What did you do last night?
What did Mei do after class?
What did they eat?
试一试: Farid: You look tired! What did you ___ all morning? Wei: I cleaned the kitchen. 补全 Farid 的问题。 (do / did / doing) 答案: do — 过去的意思已经在 did 里了，所以后面的动词保持原形。有一个选项把过去的意思放了两次，另一个是 -ing 形式，而 did 后面从来不接 -ing。