Learn Hardcore Chinese: zhōumò zài jiā chīfàn de shíhou, wǒmen chángcháng yòng hěnduō wǎn, suǒyǐ chīwán yǐhòu děi yìqǐ xǐ wǎn. - When we eat at home on weekends, we often use many bowls, so after eating we have to wash them together.

You can say 我们周末在家吃饭的时候; that’s also correct and natural. The version in your sentence just foregrounds the time/place more strongly by putting them at the very beginning.

What exactly does 在家吃饭的时候 mean, and how does the 的 work here?

在家吃饭的时候 literally breaks down as:

在家 – at home
吃饭 – eat (a meal)
的 – turns the verb phrase into something that can modify a noun
时候 – time / moment / when

So 在家吃饭的 is functioning like a relative clause describing 时候:

在家吃饭的时候 → "the time when (we) eat at home"

The 的 here is a structural particle that connects the verb phrase to 时候. It’s the same 的 you see in:

我上大学的时候 – when I was in college
你来的时候 – when you came

What’s the difference between 时候 and 的时候? Could you say 在家吃饭时 instead?

的时候 (de shíhou) is the most common spoken form for "when / at the time (that)".
时候 (shíhou) without 的 is used in some patterns (e.g. 那时候 "at that time"), but when it’s directly modified by a clause (在家吃饭), you normally add 的: 在家吃饭的时候.

You can say:

在家吃饭时 – using 时 instead of 时候.
This is more formal / written and sounds less conversational. In daily spoken Mandarin, 在家吃饭的时候 is more natural.

Why is it 用很多碗? Does 用 just mean “use”? Is this how you normally say “use many bowls / lots of dishes”?

Yes, 用 (yòng) basically means "use".
In this context:

用很多碗 → "use many bowls"

It’s a perfectly natural way to talk about how many dishes/bowls you dirty during a meal. A few similar examples:

吃火锅的时候，我们用很多盘子。
When we eat hot pot, we use many plates.
做菜的时候要用很多油。
When cooking, we need to use a lot of oil.

So 用 + quantity + noun is a very standard pattern: 用很多碗, 用两个勺子, 用一些纸 etc.

Why is there no measure word between 很多 and 碗? Shouldn’t it be 很多个碗?

Both are possible, but:

很多碗
很多个碗

They mean almost the same thing. Differences:

很多碗 is slightly more natural and fluent here; when the quantity word is vague (很多, 一些, 不少), native speakers often drop 个 if the noun itself is a countable object like 碗.
很多个碗 can feel a bit more emphatic or concrete, like you’re really focusing on the number as individual items.

In normal speech about "a lot of bowls" in this context, 很多碗 is very standard.

What does 常常 mean, and how is it different from 经常 or 总是?

常常 (chángcháng) – often, frequently
经常 (jīngcháng) – often, regularly; very close to 常常
总是 (zǒngshì) – always (or almost always)

In this sentence:

我们常常用很多碗 → "We often use many bowls."

You could almost always replace 常常 with 经常 here:

我们经常用很多碗。 – same meaning, very natural.

总是 would be stronger:

我们总是用很多碗。 – we always (pretty much without exception) use many bowls.

So 常常 / 经常 ≈ "often", while 总是 ≈ "always".

Why is it 吃完以后 instead of just 吃饭以后 or 吃了以后?

完 (wán) is a resultative complement meaning "to finish / to complete".
So:

吃完 – to finish eating
吃饭以后 – after (we) eat / after the meal
吃了以后 – after (we have) eaten

吃完以后 emphasizes the completion of the action: after we’ve finished eating up / after the meal is over.
All three are possible, but:

吃完以后 focuses on the action reaching its end (nothing left to eat).
吃饭以后 is slightly more neutral: after the eating event.
吃了以后 focuses more on the past aspect (having eaten) than on the idea of "finishing everything."

In daily conversation, 吃完以后 is very natural when you’re about to say what you do once the meal is done, like 洗碗.

Why isn’t there a 了 after 吃完? Shouldn’t completed actions use 了?

完 (wán) itself already expresses completion as a result. In many cases, that makes adding 了 unnecessary.

Compare:

我吃了。 – I ate / I have eaten. (了 marks completion/aspect)
我吃完了。 – I finished eating. (完 gives the result "finish", and 了 emphasizes that as a completed event)

In your sentence:

吃完以后 – "after (we) finish eating"

Here 以后 (after) already places it in time after completion, and 完 shows the result "finished", so 了 is not needed. You could say 吃完了以后 and it’s still correct and natural, just a bit heavier; many speakers drop the 了 in this pattern.

The 得 (děi) here means “must / have to”, right? How is this different from the other 得 (de) I’ve seen?

Yes, in 得一起洗碗, 得 (děi) is a modal verb meaning "must / have to / need to".

There are three common characters pronounced de/děi/dé that learners mix up:

得 (děi) – modal verb "must / have to"
- 我得走了。 – I have to go.
得 (de) – structural particle introducing a complement (degree/result/manner)
- 说得很好。 – (you) speak very well.
- 走得很快。 – walk very fast.
的 (de) – structural particle linking modifiers to nouns
- 我的书 – my book
- 在家吃饭的时候 – the time when (we) eat at home

In your sentence it’s clearly the first one: 得 (děi) "must":

得一起洗碗 → have to wash the dishes together.

Why is the word order 得一起洗碗 and not 一起得洗碗?

For modal verbs like 得 (děi), the basic order is:

Subject + 得 + (adverb like 一起) + Verb

So:

我们得一起洗碗。 – We have to wash the dishes together.

Putting 一起 before 得 (→ 我们一起得洗碗) is not correct in standard Mandarin. The modal comes first, then adverbs like 一起, 都, 常常 usually come after the modal and before the main verb:

我们得都去。 (more natural as 我们都得去 though – 都 has its own special behavior)
我们得先吃饭。
我们得一起洗碗。

What does 一起 add here? Could you just say 吃完以后得洗碗?

一起 (yìqǐ) means "together".

Without 一起:

吃完以后得洗碗。 – After we finish eating, (someone / we) have to wash the dishes.

With 一起:

吃完以后得一起洗碗。 – After we finish eating, we have to wash the dishes together (everyone helps).

So 一起 emphasizes that it’s a shared activity; everyone participates, not just one person.

Why is it 洗碗 and not something like 洗碗碟 or 洗盘子? Does 洗碗 cover all “doing the dishes”?

洗碗 (xǐ wǎn) literally means "wash bowls", but in everyday Mandarin it commonly means:

"to do the dishes" / "wash up after a meal"

It doesn’t strictly mean only bowls; it can include plates, chopsticks, etc., in context. Some variations:

洗碗 – very common, generic "do the dishes"
洗碗碟 – (some regions) explicitly "wash bowls and plates"
洗盘子 – specifically "wash plates"

In a typical family context, 洗碗 is the default way to say "do the dishes" after eating.

Could you say 在我的家 instead of 在家? What’s the nuance?

You could say 在我的家, but the nuance differs:

在家 – at home (usually understood as "at my/our home" from context)
在我的家 – at my home (a bit more explicit/contrastive)

In this sentence, 周末在家吃饭的时候 naturally refers to our home (since 我们 appears later). Chinese often omits possessives when it’s obvious whose home it is. Saying 在我的家 here would sound slightly unnatural and unnecessarily specific unless you are contrasting:

在学校我不做饭，在我的家才做饭。
I don’t cook at school; I cook only at my home.

So 在家 is the best choice in the general statement given in your sentence.