Learn Hardcore Chinese: dōngtiān de shíhou, fùmǔ kāi zhe nuǎnqì zài jiā kàn diànshì, zhīdào háizi ānjìng de zài fángjiān lǐ xuéxí, yě juéde hěn ānxīn. - In winter, the parents have the heating on and watch TV at home; knowing the children are quietly studying in their rooms, they also feel very at ease.

的 – links modifiers to nouns
- 冬天的时候 (time of winter)
- 漂亮的房间 (a beautiful room)
地 – links adverbial modifiers to verbs (how something is done)
- 安静地学习 (study quietly)
- 高兴地说 (say happily)
得 – links complements to verbs/adjectives (how well, how much, to what degree)
- 学习得很好 (study very well)
- 说得很快 (speak very fast)

In 安静地在房间里学习:

安静 is describing how the child studies → manner
So we use 地: 安静地学习 = to study quietly

Then 在房间里 is added as the place: quietly study in the room.

What does 着 in 开着暖气 do? Why not just 开暖气 or 开了暖气?

The particle 着 marks a continuous state – something is ongoing or in a certain state.

开着暖气: with the heating on / keeping the heating on
- Focus: the heater is on and stays on during the time they’re watching TV.

Compare:

开暖气
- Neutral: use the heating / turn on the heating (in general)
- Could describe a habit or a one-time action, depending on context.
开了暖气
- Focuses on the completed action of turning it on: they turned on the heating.
开着暖气
- Describes the state while something else is happening: they are at home watching TV with the heating on.

So 着 here sets up background: while they are watching TV at home, the heater is on the whole time.

Is the word order 开着暖气在家看电视 fixed? Can I say 在家开着暖气看电视 instead?

Chinese word order is somewhat flexible here, and several versions are natural:

Sentence version: 父母开着暖气在家看电视
Also natural: 父母在家开着暖气看电视

Both generally mean:
“The parents, with the heating on, are at home watching TV.”

Typical rough order is:

Time (冬天的时候)
Subject (父母)
Place (在家)
Manner / accompanying state (开着暖气)
Main action (看电视)

So 父母在家开着暖气看电视 matches that template nicely.

The given order 开着暖气在家看电视 is also common: it first mentions the “with the heating on” situation, then “at home”, then “watch TV”.

Unnatural would be breaking the verb and its object too much, like:

✗ 父母开着在家暖气看电视

So yes, you can say 在家开着暖气看电视, and many speakers might actually prefer that word order.

What is 在 doing in 在家看电视 and 在房间里学习? Is this the same 在 as in 我在看电视 (progressive)?

Here 在 is used as a preposition meaning “at / in”:

在家看电视 – watch TV at home
在房间里学习 – study in the room

So the pattern is:

在 + place + Verb

There is another use of 在 as a progressive marker:

我在看电视。 – I am watching TV (right now).

How to tell which it is?

If 在 is followed directly by a place word, it’s almost always “at / in”:
- 在学校学习 (study at school)
- 在家工作 (work at home)
If 在 is followed directly by a verb, it’s usually progressive:
- 在看，在吃，在学

In this sentence, 在 is always followed by a place (家, 房间里), so it’s the location usage, not the progressive one.

Why do we say 在房间里 but not 在家里 here? Is there a difference between 家 and 家里, 房间 and 房间里?

All of these are possible; the choices are partly stylistic.

家 already strongly implies “home (as a place)”
- 在家 = at home
- 在家里 is also ok, just slightly more “inside the home” feeling.
房间 is more like “room” as a unit, and 房间里 emphasizes inside the room.
- 在房间 is possible
- 在房间里 is very common and feels a bit more natural in daily speech.

In your sentence:

在家看电视 – watch TV at home (自然)
在房间里学习 – study in the room (自然)

You could also say:

在家里看电视
在房间学习

They’re grammatically fine; the meaning difference is very small. Using 里 just emphasizes “inside that space”.

How does 知道 connect to the rest of the sentence? Where is the word “that”, like in “know that the child is quietly studying…”?

Chinese doesn’t need a separate word like English “that” to introduce this kind of clause.

Structure here:

父母 … 知道 + [孩子安静地在房间里学习]，也觉得很安心。

So:

知道 takes a whole sentence as its object:
- [孩子安静地在房间里学习] = “(the) child is quietly studying in the room”

In English:

The parents … know *that the child is quietly studying in the room, and also feel at ease.*

In Chinese:

The “that” is just omitted. Word order stays the same.

Other examples with the same pattern:

我知道他今天不来。
- I know (that) he isn’t coming today.
她觉得这个办法很好。
- She thinks (that) this method is good.

No special conjunction is needed.

What does 也 do in 也觉得很安心? Could it go somewhere else?

也 means “also / too”. Here it modifies 觉得:

也觉得很安心 – also feel very at ease

Why “also”? Because the parents are:

Watching TV at home with the heating on
They know that the child is quietly studying
They also (therefore) feel very at ease

So the 也 shows that feeling at ease is an additional result or additional state.

Position:

✅ 也觉得很安心 – standard, natural
✗ 觉得也很安心 – sometimes possible in other contexts but changes focus; here it would sound odd.

Basic rule:

Place 也 before the verb it modifies:
- 我也去。(I’ll go too.)
- 他也知道。(He also knows.)
- 他们也觉得很安心。(They also feel at ease.)

Why is it 安静地在房间里学习 and not 在房间里安静地学习? Are both correct?

Both are actually possible and grammatical, with very similar meanings.

安静地在房间里学习 (your sentence)
- Focus: the manner 安静地 (quietly) comes first, then place, then verb:
- quietly, in the room, (the child) studies
在房间里安静地学习
- Focus: place first, then manner, then verb:
- in the room, (the child) quietly studies

In practice:

在房间里安静地学习 is probably a bit more common-sounding, because Chinese often likes the order:
- Time → Place → Manner → Verb

But the given 安静地在房间里学习 is still understandable and acceptable, especially in spoken style. It puts a tiny bit more emphasis on “quietly” as the way the whole situation is happening.

Wrong would be splitting things incorrectly, for example:

✗ 安静在房间里地学习

The key is:

安静地 must come right before the main verb it modifies (学习), or right before a short phrase containing that verb.

What is the nuance of 安心 here? How is it different from 放心?

Both 安心 and 放心 can be related to “feeling at ease / not worried”, but they’re not identical:

安心 (ān xīn)
- As an adjective: to feel at ease, peaceful in mind, calm
- Emotional state is stable, settled.
- In this sentence: 觉得很安心 = feel very at ease / feel reassured and peaceful.
放心 (fàng xīn)
- Literally: to let go of your heart → to stop worrying, to be relieved.
- Focuses on not needing to worry anymore.
- Common pattern: 很放心 / 放心吧 (don’t worry).

In your sentence:

觉得很安心 = they feel peaceful and at ease knowing the child is studying quietly.
You could also say 觉得很放心, which would sound like:
- they are not worried at all (about the child).

Both are plausible; 安心 feels a bit warmer / more “peaceful”, while 放心 is a bit more “not worried / relieved.”

Why do we need 很 in 很安心? Can we say just 也觉得安心?

You can say 也觉得安心, but it often sounds a bit more emphatic or contrastive, like:

“They (indeed / really) feel at ease”
or compared to another situation: “This time they actually feel at ease.”

In modern Chinese, when an adjective is used as a predicate after 是 / 很 / 觉得, we very often include 很 even when we don’t strongly mean “very”:

他(很)高。
我(很)忙。
我觉得(很)有意思。

So 很 here works like a “default link” between the subject and the adjective, smoothing the sentence:

也觉得很安心 – the most natural, neutral-sounding option
也觉得安心 – grammatically fine, but can sound more marked / contrastive depending on context.

In simple learner-style sentences, adding 很 before adjectives used as predicates is usually the safer choice unless you want a strong emphasis.

Why is there no pronoun like “they” or “him/her” before 孩子安静地在房间里学习? Should it be something like 他们知道他安静地在房间里学习?

Chinese usually doesn’t repeat pronouns if the reference is already clear from context.

We already know we’re talking about 孩子 (the child).
So the clause 孩子安静地在房间里学习 already has its subject: 孩子.
There is no need and no place for an extra 他 / 她 / 他们 there.

他们知道他安静地在房间里学习 would sound like:

They know that *he (someone else) is quietly studying in the room.*

…which introduces a different person.
Here we just want:

Parents know that the child (the one already mentioned) is quietly studying…

So the original is exactly right:

知道孩子安静地在房间里学习
- know (that) the child is quietly studying in the room

Could we also say 孩子在房间里安静地学习 instead of 孩子安静地在房间里学习? Does it change the meaning?

Yes, 孩子在房间里安静地学习 is perfectly natural, and many speakers might find that order slightly more typical:

孩子在房间里安静地学习
- Time (implicit) → Place (在房间里) → Manner (安静地) → Verb (学习)

Meaning is essentially the same: The child is quietly studying in the room.

Nuance:

孩子安静地在房间里学习
- Slightly more emphasis on the “quietly” feeling from the very beginning of the phrase.
孩子在房间里安静地学习
- Slightly clearer “in the room” first, then “quietly study”.
- Fits the common order “place before manner before verb”.

Both are acceptable; for your own speaking/writing, 孩子在房间里安静地学习 might be the easier pattern to remember.