Learn Hardcore Chinese: kāihuì jiéshù yǐhòu, tā sòng wǒ dào ménkǒu. - After the meeting ended, she walked me to the door.

Here, 送 means to escort/see someone off to a place: 送 + person + 到/去 + place.
It does not mean “to give (a gift)” in this sentence. That sense is 送给 (e.g., 送给他一本书).
Near-synonyms: 陪 (accompany, emphasis on being with), 带 (take/bring, neutral), while 送 emphasizes accompanying someone to a destination, often to say goodbye.

Why is 到 used before 门口?

到 marks the endpoint/result: arriving at the doorway. 送我到门口 = she escorted me and we reached the doorway.
With motion verbs like 送, 到 + place highlights successful arrival.

Could I use 去 instead of 到 (送我去门口)?

送我去门口 is grammatically fine but less common than 送我到门口.
Nuance: 到 emphasizes reaching the endpoint; 去 emphasizes moving toward it (arrival not highlighted). For “to the doorway,” 到 feels more natural.

Can I omit 到 and say 她送我门口?

No. You need a direction/result marker. Use:
- 送我到门口 (most natural)
- 送我去门口 (acceptable, lighter on “arrival”)
- Or change the complement: 送我出门, 送我到楼下, 送我上车.

What’s the difference between 门 and 门口?

门 = the door itself.
门口 = the doorway/entrance area (threshold/front of the door). 到门口 means “to the doorway,” not literally “onto the door.”

How does 以后 work here? Is it the same as 之后/后?

以后 after a clause means “after ….” Here it makes a time-adverbial: 开会结束以后 = after the meeting ended.
之后/后 are near-synonyms; 之后/后 often sound a bit more formal. All are fine here: 会议结束后/之后.
Note: sentence-initial 以后 can also mean “from now on” (future), so when context is past, many prefer 之后/后 or a clear past clause like 会议结束以后 to avoid ambiguity.

Do I need 了 anywhere?

Not required. Chinese doesn’t mark past tense obligatorily; the time phrase already orders the events.
Acceptable variants:
- 会议结束以后，她把我送到了门口。 (了 marks the result “arrived”)
- 会议结束了以后，她送我到门口。 (了 after 结束 emphasizes the meeting had indeed finished)
- 会议结束以后，她送我到门口。 (neutral and natural)

Is 开会结束以后 redundant? Would 会议结束以后 or 开完会以后 be better?

开会结束以后 is idiomatic and common in speech.
Alternatives:
- 会议结束以后 (nouny, neat)
- 开完会以后 (uses 完 to highlight completion; very natural)
- Very concise: 会后 (formal/written).

Why is there a comma after the time clause?

The initial clause 开会结束以后 functions as an adverbial; Chinese typically uses a comma to separate such a fronted time/condition clause from the main clause: …，她送我到门口。

Can I put the time phrase somewhere else?

Most natural: at the start: 会议结束以后，…
Also fine (slightly more formal): 她在会议结束以后送我到门口。
Avoid putting 以后 at the very end for this meaning; it belongs with the clause it modifies.

Can I use 把 here?

Yes: 她把我送到门口。 This brings 我 forward and emphasizes me as the affected object or the result. With a clear endpoint (到门口), 把 feels natural.

Can I add 去 at the end (她送我到门口去)?

Yes: …到门口去 adds a sense of motion away from the current location. It’s optional and more likely when contrasting directions (去/来), but many speakers simply say 到门口.

Is 她给我送到门口 correct?

No for the “escort” meaning. 给 marks a recipient with the “give as a gift/deliver” sense: 送给我礼物. For escorting, use 送我到…, not 给.

Can I drop 她 or 我?

Chinese allows dropping known elements:
- If the subject is obvious: 开会结束以后，送我到门口。
- Dropping 我 is rare unless context makes the object obvious: 开会结束以后，她送到门口。 sounds incomplete without a clear object.

What’s the difference between 到门口 and 在门口 (e.g., 她在门口送我)?

到门口 = to the doorway (endpoint of movement).
在门口 = at the doorway (location where the action happens). 她在门口送我 means “she saw me off at the doorway,” not “she escorted me to the doorway.”

Any pronunciation tips for this sentence?

Pinyin with tones: kāihuì jiéshù yǐhòu, tā sòng wǒ dào ménkǒu.
Tone check: kāi(1) huì(4); jié(2) shù(4); yǐ(3) hòu(4); tā(1); sòng(4); wǒ(3); dào(4); mén(2) kǒu(3).
No tricky third-tone sandhi here (the only adjacent 3rd tones are not back-to-back).