B1 Verb Tenses 12 min read 中等

过去完成进行时 (had been -ing)

Unlock past narratives by showing what was continuously happening *before* another past event.

Grammar Rule in 30 Seconds

Use this to describe an ongoing action that was happening right up until another specific moment in the past.

  • Use 'had been' plus the '-ing' form of the verb for all subjects. Example: 'I had been waiting.'
  • It emphasizes the duration or process of an action before a past cutoff. Example: 'She had been working for hours.'
  • Do not use this with stative verbs like 'know' or 'want'. Example: 'I had known him' (not 'had been knowing').
Subject + 🕰️ had been + 🏃‍♂️ Verb-ing

Overview

你是否曾觉得自己在到达起跑线之前就已经在跑马拉松了?想象一下,你正在咖啡馆等朋友。你等了一个小时。然后,你的朋友终于到了。你如何描述那一个小时的等待?你不仅仅说“我等了”。你想展现那段煎熬!你想展现那段时间的长短!这就是 Past Perfect Continuous(过去完成进行时)派上用场的地方。它是属于“坚持”的时态。它讲述的是直到过去另一个时刻为止*一直在*发生的事情。它就像电影的“幕后花絮”。虽然 Past Simple(一般过去时)告诉我们发生了什么,但这个时态告诉我们这件事持续了多久。对于 A1 级别的学习者来说,这可能感觉是一个巨大的飞跃。但可以把它看作是为你的故事增添戏剧性的一种方式。这就像是说“我很累”和“我 had been working(已经连续工作)了十个小时”之间的区别。看到区别了吗?一个是感觉,另一个是传奇。如果它看起来很长,别担心。我们在抱怨 Wi-Fi 慢或商店排长队时经常用到它。

How This Grammar Works

想象一个时间轴。你有现在(此刻)。你有过去(昨天)。现在,选出昨天下午 5 点这个点。那就是你的“锚点”。Past Perfect Continuous 描述的是在下午 5 点*之前*开始并持续*到*下午 5 点的动作。它强调过程。它非常适合解释过去某件事*为什么*看起来是那个样子。为什么你的眼睛红了?因为你整个晚上 had been staring(一直盯着)笔记本电脑屏幕。为什么地面是湿的?因为 had been raining(一直在下雨)。它连接了过去的两个点。第一个点是动作的开始。第二个点是另一件事发生时或进行观察时。它像一座桥。一边是过去,另一边也是……过去,只是稍微晚一点。如果 Past Continuous(过去进行时)是一个瞬间的快照(我正在吃),那么 Past Perfect Continuous 就是一段延时摄影。它展现了整个流动的过程。

Formation Pattern

1
构建这个时态就像做一个三层三明治。每次你都需要三层特定的结构。无论你是在谈论你自己、你的狗,还是你的朋友们,都没有关系。中间部分保持不变!
2
The Subject(主语):这是执行动作的人或物(I, You, He, She, It, We, They)。
3
The Constant Part(固定部分):始终使用 had been。这永远不会改变。它是你最好的朋友。
4
The Action Part(动作部分):选取你的主要动词并在末尾加上 -ing(例如:working, running, scrolling)。
5
公式如下:Subject + had been + [Verb + ing]
6
肯定句
I had been waiting.
7
否定句
I had not been waiting
(或 hadn't)。
8
疑问句
Had you been waiting?
9
看到了吗?它就像一套乐高积木。你只需要把零件拼在一起。不管是谁在做这件事,始终是 had been。没有 has,没有 is,没有 was。只有 had been。它实际上比现在完成进行时还要简单,因为你不需要在 hashave 之间做选择!

When To Use It

我们主要在两种情况下使用这个时态。第一,展示在另一件事之前的持续时间。想象一下你在下午 2 点开始看 Netflix 剧集。下午 6 点,你妈妈打电话来。当她打电话时,你 had been watching(已经看了)四个小时的 Netflix 了。你是在强调那四个小时的辛苦!第二,我们用它来表示因果关系。想象一下你走进一个房间,看到你的朋友气喘吁吁。你说:“你看起来很累!你刚才 Had you been running(一直在跑步)吗?”跑步发生在你看他之前,但结果(很累)在过去那个时刻是显而易见的。
  • 社交媒体语境: “在应用崩溃之前,我 had been trying(已经试着)上传我的 TikTok 一个小时了。”
  • 游戏: “当服务器宕机时,我们 had been playing(已经玩了)三个小时了。”
  • 旅行: “在到达东京之前,他们 had been flying(已经飞了)十二个小时了。”
这一切都关乎那种“直到那时”的感觉。如果你想听起来像一个地道的英语使用者,在星巴克抱怨长时间的等待,这就是你的工具。

Common Mistakes

即使是专家有时也会被自己的鞋带绊倒!以下是需要注意的重大错误。
  1. 1丢失了 Been:很多人忘记了 been 这个词。他们说 I had working。不!这听起来像个坏掉的机器人。你需要 been 来填补这个空隙。
  2. 2状态动词的混乱:有些动词不喜欢 -ing。我们称之为“状态动词”。像 know, like, wantbelieve 这样的词。你不能说
    I had been knowing him
    。只能说
    I had known him
    。对这些词使用 Past Perfect Simple(过去完成时)。
  3. 3时态混淆:谈论过去时不要使用 has been。如果故事昨天结束了,请保持使用 hadHas 是用于现在仍在发生的事情。
  4. 4拼写陷阱:记住添加 -ing 的规则。如果一个单词以不发音的 'e' 结尾(如 dance),去掉 'e' (dancing)。如果是短元音 + 辅音(如 run),双写辅音 (running)。
记住:如果是一种感觉或想法,不要使用 -ing 形式。如果是一个你可以看到的动作(如跑步或打字),那就尽管使用它!

Contrast With Similar Patterns

这里变得有趣了。这与 Past Continuous(“我正在工作”)有何不同?
  • Past Continuous:关注一个特定的时刻。“晚上 8 点,我 was working(正在工作)。”(也许我 7:59 开始,也许 5:00 开始。我们不知道)。
  • Past Perfect Continuous:关注通往某个时刻的时间。“到晚上 8 点时,我 had been working(已经工作)三个小时了。”
那么 Past Perfect Simple(“我已经工作过”)呢?
  • Past Perfect Simple:关注*完成*或结果。“到晚上 8 点时,我 had finished(已经完成了)我的工作。”
  • Past Perfect Continuous:关注*过程*和持续时间。“当灯熄灭时,我 had been finishing(一直在完成)我的工作。”
这样想吧:Past Simple 是比赛的得分。Past Perfect Continuous 是比赛过程中的汗水和努力。

Quick FAQ

问:总是使用 had been 吗?
答:是的!对于每个主语(我、你、他、我们),它都保持完全一样。它是英语语法中最忠实的部分。
问:我可以把它用于短动作吗?
答:通常不行。我们把它用于需要时间的事情,如 studying, waitingsleeping。你不会说“我眨眼了一个小时”,除非你有一个非常奇怪的爱好。
问:必须是很长的时间吗?
答:不一定!它只需要是一个持续的动作。“当我找到钥匙时,我 had been looking(已经找了)两分钟了”是完全可以的。
问:它正式吗?
答:它既用于正式写作,也用于非正式的短信。它只是讲述故事的一种精确方式。
问:最简短的表达方式是什么?
答:在口语中,我们使用缩写,如 I'd been, you'd been, she'd been。这在 WhatsApp 上快得多!
问:我可以把它用于将来吗?
答:不行,这严格来说是用于过去的。对于将来,我们使用 will have been。但先别让你的脑袋疼了!
问:为什么不直接使用过去时呢?
答:你可以,但你会失去那种“韵味”。说“我等了两个小时”是一个事实。说“我 had been waiting(等了两个小时)”是一种感觉。它展示了你付出了多少努力!
问:动作必须停止吗?
答:通常在第二个过去事件发生时动作会停止,但并非总是如此。有时它会继续。语境才是关键!

Conjugation of 'To Work'

Subject Auxiliary Been Verb-ing
I
had
been
working
You
had
been
working
He/She/It
had
been
working
We
had
been
working
They
had
been
working

Contractions

Full Form Contraction Negative Contraction
I had been
I'd been
I hadn't been
You had been
You'd been
You hadn't been
He had been
He'd been
He hadn't been
She had been
She'd been
She hadn't been
It had been
It'd been
It hadn't been
We had been
We'd been
We hadn't been
They had been
They'd been
They hadn't been

Meanings

A verb tense used to show that an action started in the past and continued up until another time in the past.

1

Duration before a past event

To emphasize how long an activity was in progress before something else happened.

“I had been studying for three hours before I finally understood the concept.”

“We had been driving since morning when the car broke down.”

2

Cause of a past result

To show the cause of a specific state or situation in the past.

“The ground was wet because it had been raining.”

“He was exhausted because he had been working out all morning.”

3

Repeated past actions

To describe a habit or repeated action that occurred leading up to a past point.

“I had been visiting that cafe every day until it closed down.”

“They had been sending letters for years before they finally met.”

Reference Table

Reference table for 过去完成进行时 (had been -ing)
Form Structure Example
Affirmative
Subject + had been + V-ing
I had been waiting for an hour.
Negative
Subject + had not been + V-ing
She hadn't been sleeping well.
Question
Had + subject + been + V-ing?
Had they been talking about me?
Short Answer (+)
Yes, subject + had.
Yes, I had.
Short Answer (-)
No, subject + hadn't.
No, they hadn't.
Wh- Question
Wh- + had + subject + been + V-ing?
How long had it been raining?

正式程度

正式
The employee was exhausted as he had been performing his duties for twelve consecutive hours.

The employee was exhausted as he had been performing his duties for twelve consecutive hours. (Workplace/Social)

中性
He was tired because he had been working for twelve hours.

He was tired because he had been working for twelve hours. (Workplace/Social)

非正式
He was wiped out; he'd been working for like twelve hours straight.

He was wiped out; he'd been working for like twelve hours straight. (Workplace/Social)

俚语
He was dead tired 'cause he'd been grinding for twelve hours.

He was dead tired 'cause he'd been grinding for twelve hours. (Workplace/Social)

Past Perfect Continuous Timeline

Past Perfect Continuous

Focus

  • Duration How long?
  • Process The activity

Time

  • Before Past Earlier than another past event

Past Continuous vs. Past Perfect Continuous

Past Continuous
I was eating when he arrived. Focus on the moment of arrival.
Past Perfect Continuous
I had been eating for an hour when he arrived. Focus on the time before arrival.

按水平分级的例句

1

I had been working.

I had been working.

2

She had been running.

She had been running.

3

Had you been sleeping?

Had you been sleeping?

4

They had not been eating.

They had not been eating.

1

It had been raining for hours.

It had been raining for hours.

2

He was tired because he had been studying.

He was tired because he had been studying.

3

We had been waiting for the bus.

We had been waiting for the bus.

4

Had they been playing football?

Had they been playing football?

1

I had been living in London for a year when I met her.

I had been living in London for a year when I met her.

2

They had been arguing for a long time before they stopped.

They had been arguing for a long time before they stopped.

3

She had been practicing the violin all day.

She had been practicing the violin all day.

4

Why had he been crying before the party?

Why had he been crying before the party?

1

The company had been struggling for months before it finally closed.

The company had been struggling for months before it finally closed.

2

I realized that someone had been following me.

I realized that someone had been following me.

3

Had you been expecting the news for a while?

Had you been expecting the news for a while?

4

We hadn't been looking for a new house, but we found one.

We hadn't been looking for a new house, but we found one.

1

The researchers had been conducting experiments for years without success.

The researchers had been conducting experiments for years without success.

2

By the time the police arrived, the suspects had been hiding in the basement.

By the time the police arrived, the suspects had been hiding in the basement.

3

She felt as though she had been wandering in a dream.

She felt as though she had been wandering in a dream.

4

Had the government been ignoring the warnings, the crisis would have been worse.

Had the government been ignoring the warnings, the crisis would have been worse.

1

The philosopher had been grappling with the concept of 'being' for his entire career.

The philosopher had been grappling with the concept of 'being' for his entire career.

2

The engine had been emitting a faint clicking sound, which the driver ignored.

The engine had been emitting a faint clicking sound, which the driver ignored.

3

It was evident that the manuscript had been being edited by multiple hands.

It was evident that the manuscript had been being edited by multiple hands.

4

For weeks, a sense of unease had been permeating the small community.

For weeks, a sense of unease had been permeating the small community.

容易混淆

Past Perfect Continuous (had been -ing) 对比 Past Perfect Simple

Learners often use the Continuous form when they should use the Simple form for completed actions.

Past Perfect Continuous (had been -ing) 对比 Past Continuous

Both describe ongoing actions in the past.

Past Perfect Continuous (had been -ing) 对比 Present Perfect Continuous

Learners use 'have been' when they should use 'had been' because they are thinking about the present.

常见错误

I had working.

I had been working.

You must include 'been' in this tense.

I was been working.

I had been working.

The auxiliary is 'had', not 'was'.

I had been work.

I had been working.

The main verb must have the -ing ending.

He have been working.

He had been working.

In the past perfect, 'have' always becomes 'had'.

Had you working?

Had you been working?

Questions still need the word 'been'.

I had been knowing him.

I had known him.

'Know' is a stative verb and cannot be continuous.

It had been rain.

It had been raining.

The verb needs the -ing suffix for continuous tenses.

I had been seeing that movie before.

I had seen that movie before.

Use Past Perfect Simple for completed actions/experiences.

They had been starting the game when I arrived.

They had started the game when I arrived.

'Start' is usually an instantaneous action, not a continuous one.

I hadn't being working.

I hadn't been working.

Confusing 'been' (past participle) with 'being' (present participle).

I had been having a car.

I had had a car.

'Have' as possession is stative.

句型

I had been ___ for ___ when ___.

The ___ was ___ because it had been ___.

Had you been ___ before you ___?

By the time ___, they had been ___ since ___.

Real World Usage

Job Interviews common

Before my last role, I had been working as a freelance consultant for two years.

Doctor's Appointment very common

I had been feeling dizzy for a week before I decided to come in.

Social Media Storytelling occasional

I'd been wanting to visit this cafe forever, and it finally happened!

Police Reports common

The witness stated that the car had been idling for ten minutes before the incident.

Travel Vlogs common

We'd been hiking since 5 AM to catch this sunrise.

Customer Support occasional

I had been trying to log in for an hour before the system locked me out.

💡

The 'Evidence' Rule

If you see a result in the past (e.g., wet ground, tired eyes), use the Past Perfect Continuous to explain the cause.
⚠️

Stative Verb Alert

Never use 'had been -ing' with verbs like 'know', 'believe', 'own', or 'love'. Use the Past Perfect Simple instead.
🎯

Reported Speech

When reporting what someone said in the Present Perfect Continuous, always shift it to the Past Perfect Continuous.
💬

Softening Excuses

Using this tense can make an excuse sound more valid because it emphasizes the effort you were making.

Smart Tips

Use the Past Perfect Continuous to provide the reason.

I was tired. I ran. I was tired because I had been running.

Check if you should use Past Perfect Continuous instead of Past Simple.

I lived there for five years when the war started. I had been living there for five years when the war started.

Immediately switch to the Simple form.

I had been believing him until that day. I had believed him until that day.

Use this tense to set the scene before the main action starts.

The sun shone. Birds sang. Then the phone rang. The sun had been shining and birds had been singing all morning. Then the phone rang.

发音

/aɪd bɪn/

Contraction of 'Had'

In natural speech, 'had' is almost always contracted to ''d'.

/bɪn/

Reduction of 'Been'

The word 'been' is often unstressed and sounds like 'bin'.

Emphasis on Duration

I had been waiting for HOURS! (Rising intonation on 'hours')

Expresses frustration or highlights the length of time.

记住它

记忆技巧

HAD BEEN -ING: History's Action, Duration, Background, Earlier, Evidence, Now-not (it stopped).

视觉联想

Imagine a long, thick rope (the continuous action) that suddenly hits a wall (the second past event). The rope represents the 'had been -ing' part.

Rhyme

To show how long a past thing went, 'Had been -ing' is the tense you've sent!

Story

I was tired. Why? I had been running. I was wet. Why? It had been raining. I was smart. Why? I had been studying.

Word Web

hadbeenwaitingsinceforbeforeuntil

挑战

Write three sentences about what you had been doing before you started this lesson.

文化笔记

British speakers frequently use this tense to justify social lateness or explain background context in polite conversation.

In casual American speech, the Past Perfect Continuous is sometimes replaced by the Past Continuous if the 'before' relationship is clear from context.

In academic history or literature reviews, this tense is vital for establishing the 'state of the world' before a specific historical turning point.

The 'perfect' aspect comes from the Latin 'perfectum' (completed), while the 'continuous' aspect developed later in Middle English to emphasize ongoing action.

对话开场白

What had you been doing right before you started this English lesson?

Think of the last time you were really tired. Why? What had you been doing?

Before you moved to your current home, where had you been living?

Tell me about a project you finished. What had you been working on for a long time?

日记主题

Describe a day that went wrong. Use the Past Perfect Continuous to explain the background events.
Write about a historical event. What had been happening in the world before that event took place?
Imagine you are a detective. Describe a crime scene and what you think the suspects had been doing before you arrived.
Write a letter to your younger self. Describe what you had been dreaming about before your life changed.

常见错误

Incorrect

正确


Incorrect

正确


Incorrect

正确


Incorrect

正确

Test Yourself

Complete the sentence with the Past Perfect Continuous form of the verb in brackets.

They ___ (wait) for over an hour before the train arrived.

✓ Correct! ✗ Not quite. Correct answer: had been waiting
We use 'had been waiting' to show the duration before the train arrived.
Choose the correct sentence. 多项选择

Which sentence is grammatically correct?

✓ Correct! ✗ Not quite. Correct answer: I had known her for a long time.
'Know' is a stative verb and cannot be used in the continuous form.
Find the error in the following sentence. Error Correction

Find and fix the mistake:

She was tired because she has been running.

✓ Correct! ✗ Not quite. Correct answer: has
Since the first part is in the past ('was'), the second part should be 'had been running'.
Rewrite the sentence using the Past Perfect Continuous. Sentence Transformation

It started raining two hours ago. It was still raining when I left. (It...)

✓ Correct! ✗ Not quite. Correct answer: It had been raining for two hours when I left.
This combines the duration and the past reference point.
Complete the dialogue. Dialogue Completion

A: Why were your hands so dirty? B: I ___ in the garden.

✓ Correct! ✗ Not quite. Correct answer: had been working
The dirty hands are the result of a prior continuous action.
Is the following rule true or false? True False Rule

You can use the Past Perfect Continuous with the verb 'want'.

✓ Correct! ✗ Not quite. Correct answer: False
'Want' is a stative verb.
Which tense is used here: 'I'd been looking for my phone'? Grammar Sorting

✓ Correct! ✗ Not quite. Correct answer: Past Perfect Continuous
'I'd been' is the contraction for 'I had been'.
Match the cause to the result. Match Pairs

Match each item on the left with its pair on the right:

✓ Correct! ✗ Not quite. Correct answer: 1-Red eyes, 2-Smell of food, 3-Sweaty
These are the logical results of the actions.

Score: /8

练习题

8 exercises
Complete the sentence with the Past Perfect Continuous form of the verb in brackets.

They ___ (wait) for over an hour before the train arrived.

✓ Correct! ✗ Not quite. Correct answer: had been waiting
We use 'had been waiting' to show the duration before the train arrived.
Choose the correct sentence. 多项选择

Which sentence is grammatically correct?

✓ Correct! ✗ Not quite. Correct answer: I had known her for a long time.
'Know' is a stative verb and cannot be used in the continuous form.
Find the error in the following sentence. Error Correction

Find and fix the mistake:

She was tired because she has been running.

✓ Correct! ✗ Not quite. Correct answer: has
Since the first part is in the past ('was'), the second part should be 'had been running'.
Rewrite the sentence using the Past Perfect Continuous. Sentence Transformation

It started raining two hours ago. It was still raining when I left. (It...)

✓ Correct! ✗ Not quite. Correct answer: It had been raining for two hours when I left.
This combines the duration and the past reference point.
Complete the dialogue. Dialogue Completion

A: Why were your hands so dirty? B: I ___ in the garden.

✓ Correct! ✗ Not quite. Correct answer: had been working
The dirty hands are the result of a prior continuous action.
Is the following rule true or false? True False Rule

You can use the Past Perfect Continuous with the verb 'want'.

✓ Correct! ✗ Not quite. Correct answer: False
'Want' is a stative verb.
Which tense is used here: 'I'd been looking for my phone'? Grammar Sorting

✓ Correct! ✗ Not quite. Correct answer: Past Perfect Continuous
'I'd been' is the contraction for 'I had been'.
Match the cause to the result. Match Pairs

1. Had been crying / 2. Had been cooking / 3. Had been exercising

✓ Correct! ✗ Not quite. Correct answer: 1-Red eyes, 2-Smell of food, 3-Sweaty
These are the logical results of the actions.

Score: /8

Practice Bank

12 exercises
Choose the correct form to complete the sentence. 填空

The children's toys were all over the floor because they ___ playing there.

✓ Correct! ✗ Not quite. Correct answer: had been
Find and fix the mistake in the sentence. Error Correction

I was hungry because I hadn't eating all day.

✓ Correct! ✗ Not quite. Correct answer: I was hungry because I hadn't been eating all day.
Which sentence is grammatically correct? 多项选择

Choose the correct sentence:

✓ Correct! ✗ Not quite. Correct answer: She had been living in Berlin for three years when she met him.
Type the correct English sentence. 翻译

Translate into English: 'Habíamos estado esperando el autobús durante media hora cuando llegó.'

✓ Correct! ✗ Not quite. Correct answer: ["We had been waiting for the bus for half an hour when it arrived.","We'd been waiting for the bus for half an hour when it arrived."]
Put the words in order to form a correct sentence. Sentence Reorder

Arrange these words into a sentence:

✓ Correct! ✗ Not quite. Correct answer: The children had been playing all morning.
Match the beginning of the sentence with its correct ending. Match Pairs

Match the clauses to form logical sentences:

✓ Correct! ✗ Not quite. Correct answer: matched
Complete the sentence with the correct form of the verb in parentheses. 填空

Before the fire, the old building ___ (stand) there for centuries.

✓ Correct! ✗ Not quite. Correct answer: had been standing
Identify and correct the grammatical error. Error Correction

When I saw him, he looked like he has been crying.

✓ Correct! ✗ Not quite. Correct answer: When I saw him, he looked like he had been crying.
Select the sentence that uses the Past Perfect Continuous correctly. 多项选择

Which sentence is correct?

✓ Correct! ✗ Not quite. Correct answer: We had known each other for years before we became close.
Type the correct English sentence. 翻译

Translate into English: 'Ella había estado estudiando español desde la universidad.'

✓ Correct! ✗ Not quite. Correct answer: ["She had been studying Spanish since university.","She'd been studying Spanish since university."]
Unscramble the words to form a coherent sentence. Sentence Reorder

Arrange these words into a sentence:

✓ Correct! ✗ Not quite. Correct answer: They had been waiting for hours when the bus finally arrived.
Connect the first part of the sentence to its logical conclusion. Match Pairs

Match the beginnings with the correct endings:

✓ Correct! ✗ Not quite. Correct answer: matched

Score: /12

常见问题 (8)

The Simple form (`had worked`) focuses on completion or a result. The Continuous form (`had been working`) focuses on the duration or the process itself.

Yes! They are very common. Use `for` for a period of time (for two hours) and `since` for a starting point (since 5 PM).

It is grammatically possible in the passive voice, but it sounds very awkward. It's better to say `The house was being built` or `They had been building the house`.

Because `know` is a stative verb. Stative verbs describe a state that doesn't change, so they don't have a 'continuous' aspect in English.

Put `not` between `had` and `been`. The contraction is `hadn't been`.

Use `Past Continuous` for an action that was happening *at* a specific time. Use `Past Perfect Continuous` for an action that was happening *up until* a specific time.

It is moderately common, especially when telling stories or explaining why you were in a certain state (tired, late, etc.).

No! That's the best part. It is always `had been` for I, you, he, she, it, we, and they.

Scaffolded Practice

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Mastery Progress

Needs Practice

Improving

Strong

Mastered

In Other Languages

Spanish high

Pluscuamperfecto de subjuntivo/indicativo continuo

Spanish uses it slightly less frequently than English in casual speech.

French moderate

Plus-que-parfait + en train de

French does not have a dedicated single tense for this aspect.

German low

Plusquamperfekt + schon/lange

German lacks a continuous verb form entirely.

Japanese partial

〜ていた (~te ita)

The distinction between Past Continuous and Past Perfect Continuous is made through context/adverbs, not the verb itself.

Arabic moderate

كان قد + present verb (kana qad...)

The word order and auxiliary usage are quite different.

Chinese none

一直 (yīzhí) + verb + 过 (guò)

Tense is indicated by context and particles, not verb changes.

Learning Path

Prerequisites

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