Learn Hardcore Chinese: wǒmen huílái le,wǒmen dōu hěn gāoxìng.

Here 了 is sentence-final (change-of-state) 了. It announces a new situation: “We’re back now.” It’s not just “past tense.” Compare: 下雨了 “It’s started raining.”

Can I just say 我们回来?

Not to announce arrival. 我们回来 without 了 sounds habitual or future (“we come back / will come back”). To say “We’re back,” use 我们回来了.

How do I say “We haven’t come back yet”?

Use 没(有): 我们还没回来。/ 我们还没有回来。
Don’t use 不 here: 我们不回来 means “we won’t come back” or “we don’t come back (in general).”

Why is 都 after 我们? Where does 都 go?

Pattern: Subject + 都 + Predicate. It comes right after the group it quantifies and before the verb/adj:

我们都很高兴。
我们都回来了。

Do I have to use 都?

No.

我们很高兴 = “We’re happy” (group statement).
我们都很高兴 = “Every one of us is happy” (distributive emphasis).
Use 都 when you want to stress “all/both.”

Does 很 really mean “very” here?

Often it’s just a neutral linker before an adjective-predicate. 我们都很高兴 usually reads as “we’re (all) happy,” not strongly “very.” For stronger emphasis, use 非常/特别.

Why no 是 before 很高兴?

Adjectives function like stative verbs, so you don’t use 是 to link them: 我们很高兴 (not 我们是很高兴). You use 是 to link to nouns: 我们是学生.
Note: 是很高兴 can appear in contrastive focus, but that’s marked.

Can I drop the second 我们?

Yes. If the subject stays the same, omit it in the second clause: 我们回来了，都很高兴。

Can I connect the clauses with 和 (“and”)?

No. 和 links nouns, not clauses. Use a comma or a connector:

我们回来了，所以我们都很高兴。
因为我们回来了，我们都很高兴。

回来 vs 回去 — which one and when?

回来: returning toward the speaker’s location (“come back (here)”): 我们回来了。
回去: returning away from the speaker (“go back (there)”): 我们回去了。
Choice depends on the speaker/listener’s vantage point.

How do I include the destination/place?

Common, natural options:

Destination only: 我们回家了。/ 我们回公司了。
Emphasize arrival: 我们回到家了。 (also very common: 我们到家了 “We’ve arrived home.”)
Use bare 回来 when the destination is “here”: 我们回来了。

Can I add 已经 (“already”)?

Yes: 我们已经回来了，我们都很高兴。 It highlights that the return is completed (often earlier than someone expected).

What’s the difference among 高兴, 开心, and 快乐?

高兴: glad/happy about something; very common and neutral.
开心: cheerful/pleased; more colloquial.
快乐: happiness in a more formal or lasting sense; used in greetings (e.g., 生日快乐).
Here you can also say: 我们都很开心。

How would I say “We’re all happy now (as a change from before)”?

Add sentence-final 了 to the second clause: 我们都很高兴了。 This marks a new situation (e.g., we weren’t happy earlier, but now we are).

Where does negation go with 都?

我们都不高兴。 Everyone is unhappy.
我们不都高兴。 Not everyone is happy (some are, some aren’t). This form is rarer; you often clarify with 并不都: 我们并不都高兴。

Any pronunciation tips for this sentence?

我们 wǒmen: neutral tone on men.
回 huí (2nd), 来 lái (2nd).
了 le: neutral tone (not liǎo).
都 dōu: 1st tone.
高兴 gāoxìng: gāo (1st), xìng (4th).

Is 回来 one word or two? Can I split it?

It’s a verb + directional complement (回 + 来), functioning as one unit. You can make ability forms: 回得来/回不来 (“be able/unable to come back”). Don’t insert adverbs between 回 and 来; put things like 都/也 before the whole verb phrase: 我们都回来了。