Learn Hardcore Chinese: lǎoshī zài zhōngwén kè shàng gěi wǒmen jiǎng gùshi. - In Chinese class, the teacher tells us stories.

在 marks the general location or situation.
上 here is not literally “on top of”, but a grammatical marker meaning “during / in the context of (this class/meeting/activity)”.

Saying 在中文课 by itself can be understood, but for “during (a specific) Chinese class”, 在中文课上 (or putting 中文课上 at the start: 中文课上，老师…) is much more natural.

What is the role of 在 here? Is it the same 在 as in “to be doing something” (progressive aspect)?

在 has two main uses that learners see early:

Location marker: 在 + place = “at / in / on (a place)”.
Progressive marker: 在 + verb = “be doing (something)”.

In this sentence, 在 is followed by 中文课上, a place/time-like phrase, not a verb. So here it is the location/situation marker, meaning “in Chinese class / during Chinese class”, not the progressive “be doing” usage.

What exactly does 上 mean in 课上? I thought 上 means “up” or “to attend class”.

上 does have meanings like “up, above” and the verb “to attend (class), to go to”. But in 课上, it works as a postposition indicating the context or occasion:

课 = class, lesson
课上 = “in class, during the class (session)”

Some similar patterns:

在会上 – during the meeting / at the meeting
在路上 – on the road / on the way
在考试中 / 在考试时 – during the exam

So in 中文课上, 上 is part of a fixed-ish pattern meaning “in the context of that class”.

Why is the word order 老师在中文课上给我们讲故事? Could we say 老师给我们在中文课上讲故事?

Chinese typically orders information like this:

Subject + (Time) + (Place) + (Beneficiary/Target 等) + Verb + Object

So:

老师 – subject
在中文课上 – where/when (situation)
给我们 – beneficiary (“to us”)
讲故事 – main action

You can say 老师给我们在中文课上讲故事, but it is less natural and sounds a bit clunky. The usual, smooth order is to set the scene first (in Chinese class), then say what the teacher does there (tells us stories).

What is 给 doing here? I thought 给 means “to give”.

给 can be both a verb (“to give”) and a kind of preposition / coverb meaning “to / for (someone)”.

In this sentence, 给我们 means “to us / for us”, marking us as the beneficiary of the action:

Core action: 讲故事 – tell stories
Beneficiary: 给我们 – to us

So the structure 给 + person + Verb + Object is like English “tell a story to us / for us”, where “give” is no longer a literal “hand over” action.

Could I replace 给我们 with 对我们, like 对我们讲故事?

For “tell (someone) a story”, 给 is the natural choice:

给我们讲故事 – the teacher tells us a story (for our benefit).

对 is often used with 说 / 讲话 / 表示 / 道歉 etc.:

对我们说 – speak to us
对老师道歉 – apologize to the teacher

对我们讲故事 is understandable but sounds unusual; native speakers normally say 给我们讲故事.

What is the difference between 讲, 说, and 告诉 here? Why 讲故事 and not 说故事 or 告诉故事?

They all relate to speaking but with different typical uses:

讲 – “to narrate / to explain / to tell (in detail)”
- Common with 故事 (story), 道理 (principle), 笑话 (joke):
  - 讲故事, 讲道理, 讲笑话
说 – “to say / to speak / to talk”
- Common in shorter utterances or general speaking:
  - 说话 (talk), 说中文 (speak Chinese)
告诉 – “to tell someone (some information)”
- Pattern: 告诉 + someone + something
  - 告诉我一个秘密 – tell me a secret

So 讲故事 is the fixed, idiomatic choice meaning “tell a story”. 说故事 is rarely used in Mainland Mandarin but is more common in some regional varieties (e.g. Taiwan). 告诉故事 is incorrect.

Why is there no measure word like 一个? Why not 讲一个故事 instead of just 讲故事?

Both are possible, with a nuance difference:

讲故事 – “tell stories / tell a story” in a general or habitual sense.
讲一个故事 – “tell one story”, emphasizing a specific instance/number.

In a sentence like 老师在中文课上给我们讲故事, it can easily mean “(often/usually) tells us stories in Chinese class” or “tells us a story” depending on context. If you want to stress that it was one single story, say 讲一个故事.

How do we know if this sentence is past, present, or future? There is no tense marker like in English.

Mandarin does not mark tense the way English does. 老师在中文课上给我们讲故事 is time-neutral by itself.

The time is usually shown by:

Time words: 昨天, 现在, 明天, 上次, 每次, etc.
Context or surrounding sentences.

For example:

昨天老师在中文课上给我们讲故事。 – Yesterday the teacher told us a story in Chinese class.
现在老师在中文课上给我们讲故事。 – Right now the teacher is telling us a story in Chinese class.
明天老师在中文课上给我们讲故事。 – Tomorrow the teacher will tell us a story in Chinese class.

Should there be a 了 to show that the story-telling is finished, like 讲了故事?

You add 了 when you want to highlight that the action is completed or that it happened (at least once):

老师在中文课上给我们讲了一个故事。
– The teacher told us a story (and it’s done).

Without 了, the sentence can:

Describe a habit/routine:
- “The teacher (regularly) tells us stories in Chinese class.”
Or be a neutral statement about an event, with the time understood from context.

So 了 is optional and depends on what nuance you want to express.

Why do we need 们 in 我们? Could we just say 我 to mean “we”?

In Mandarin:

我 = “I / me”
我们 = “we / us”

You generally must add 们 to make the plural for personal pronouns (我 → 我们, 你 → 你们, 他 → 他们).

So 老师在中文课上给我讲故事 means “The teacher tells me a story”, while 给我们讲故事 clearly means “tells us a story”.

Where would I put a time word like “yesterday” or “every day” in this sentence?

The general pattern is:

Subject + (Time) + (Place) + (Beneficiary) + Verb + Object

So you can say:

老师昨天在中文课上给我们讲故事。 – The teacher yesterday in Chinese class told us stories.
老师每天在中文课上给我们讲故事。 – The teacher every day in Chinese class tells us stories.

You can also put the time at the very beginning as a topic:

昨天，老师在中文课上给我们讲故事。
每天，老师在中文课上给我们讲故事。

How do I say “The teacher is currently telling us a story in Chinese class” using 正在?

Use 正在 before the verb phrase to stress the action is in progress right now:

老师正在在中文课上给我们讲故事。 – grammatically possible but sounds a bit redundant with two 在.
More natural:
老师正在给我们讲故事，在中文课上。
Or rearrange slightly: 现在老师在中文课上正在给我们讲故事。

Many speakers simply say:

老师在中文课上正在给我们讲故事。

Key idea: 正在 + 给我们讲故事 marks the ongoing action: “is in the middle of telling us a story”.

What is the difference between 中文 and 汉语 in 中文课? Could it also be 汉语课?

Both can be used, but there are subtle preferences:

中文 – “Chinese (language and writing as a subject)”
- 中文课 is very common in schools, especially when the focus includes reading, writing, literature.
汉语 – “the Chinese (Han) language”
- 汉语课 is often used in contexts of teaching Chinese as a foreign language.

In practice, many people use 中文课 and 汉语课 interchangeably for “Chinese class”, especially in everyday speech. The sentence would still be grammatical and natural with 汉语课上 instead of 中文课上.