Learn Hardcore Chinese: wǒmen yíhuìr zài gōngyuán jiànmiàn. - We’ll meet at the park in a little while.

我们 (subject) + 一会儿 (time) + 在公园 (place) + 见面 (action). You can also front the time as a topic: 一会儿我们在公园见面. Avoid putting the time after the place in this kind of sentence (e.g., 我们在公园一会儿见面 is unnatural in neutral tone).

Does 在 here mean “be doing” (progressive), or does it just mark location?

Here 在 (zài) is a location marker meaning “at/in.” It attaches to a place noun: 在公园 “at the park.” It is not the progressive marker as in 在看书 “be reading.” You can tell because it’s followed by a noun (公园), not directly by a verb.

Can I drop 在 and say 我们一会儿公园见面?

In a full sentence, keep 在: 我们一会儿在公园见面. In very casual, elliptical speech, people do say things like 三点公园见 or 门口见, but that’s a clipped note/imperative style, not a complete sentence.

Can 见面 take a direct object? Why not 见面他?

见面 (jiànmiàn) is intransitive and literally means “to meet (each other),” so it cannot take a direct object. To specify who you meet, use 跟/和 + person:

我们一会儿在公园跟他见面。
Do not say 见面他.

What’s the difference between 见 and 见面?

见 (jiàn) = “see/meet,” can take an object: 我见了他 “I saw/met him.” Also used in set phrases like 明天见 “See you tomorrow.”
见面 (jiànmiàn) = “meet each other” (reciprocal/intransitive): 我们见了面 “We met (each other).”
For arranged meetups with mutuality, 见面 is very common. Both can be fine depending on focus:
Arranged: 我们明天见面。
One-sided seeing or requesting: 我要见他。

Is 见面 a separable verb? Where do I put 了/过/measure words?

Yes, it’s a separable verb (离合词). You can insert particles or measures:

Experience: 我们见过面。 “We’ve met before.”
Completion: 我们见了面。
One time: 我们见一面。 / 我们见过两次面。

Can I say 见一下, 见一面, or 见个面? Are they different?

All three are common and slightly different in feel:

见一下: meet briefly (polite, neutral).
见一面: meet once (counts one meeting).
见个面: casual/colloquial “have a quick meet-up.”
Avoid the non-native-sounding 见面一下; use 见一下 or 见个面 instead.

Do I need 了 or other aspect markers in this future plan?

No. For a scheduled future, a time word like 一会儿 is enough. 了 would be used after the meeting happens: 我们终于见面了！ You can add 就 to stress imminence: 我们一会儿就见面。

Does 一会儿 (yíhuìr) mean “in a moment” or “for a moment”?

Both, depending on position:

Before the clause = “in a little while” (time adverbial): 我们一会儿在公园见面。
After a verb = “for a short while” (duration): 聊一会儿。
It can also appear in pairs for alternation: 一会儿下雨，一会儿又晴。

Why is 一 pronounced yí in 一会儿 (yíhuìr)? And what about the -r?

Tone sandhi: 一 (yī) changes to yí before a fourth-tone syllable (here 会 huì). So yíhuìr is correct. The final 儿 (-r) is the northern “erhua” sound; in many southern regions (e.g., Taiwan), people say 一会 (yíhuì) without the -r. Both are acceptable regionally.

Any tone sandhi issues with 见面 (jiànmiàn)?

Both syllables are fourth tone. Unlike third-tone sandhi, fourth + fourth doesn’t require a change. Just keep both falling; in natural speech the first may be slightly lighter.

Can I add 会 to mark the future, as in 我们一会儿会在公园见面?

You can, but it’s usually unnecessary here. 会 adds a sense of likelihood/prediction. For a plan/arrangement, native speech typically omits 会: 我们一会儿在公园见面。 Use 会 if you’re predicting rather than scheduling.

How do I make this a suggestion or a confirmation question?

Suggestion (soften with a particle): 我们一会儿在公园见面吧。
Seek agreement: 我们一会儿在公园见面，好吗？
Yes/no confirmation: 我们一会儿在公园见面吗？

Should it be 在公园 or 在公园里?

Both are fine.

在公园: general “at the park,” neutral.
在公园里: slightly emphasizes “inside the park” (as opposed to, say, at the gate). Use 里 when you want to stress being inside an area.

Can I say 去公园见面? What’s the nuance?

Yes: 我们一会儿去公园见面 emphasizes the action of going there. Without 去, the destination is implied but the sentence focuses on the meeting itself: 我们一会儿在公园见面。

Where do I put the person I’m meeting (with 跟/和)?

Both orders are common:

我们一会儿跟他在公园见面。
我们一会儿在公园跟他见面。 They mean the same; minor differences in emphasis only.

How do I negate or change the meeting place?

Use 不 for simple negation, typically with contrast:

我们一会儿不在公园见面，在图书馆见面。 If giving instructions, you might use 别 for “don’t”: 别在公园见面了，改在咖啡店。

Is spacing like this normal in Chinese?

No. Standard Chinese writing doesn’t use spaces between words. It would be written as 我们一会儿在公园见面。 The spaces in your example are for learning/segmentation.

Any synonyms for 见面 I could use?

碰面 (pèngmiàn): casual “meet/bump into”; can also be arranged.
会面 (huìmiàn): more formal “meet (for official/business).”
见 alone in set phrases: 三点见 “See you at three,” 明天见.

How do I say “in 15 minutes/at 3 p.m.” more precisely?

In 15 minutes: 我们十五分钟后在公园见面。 (also 十五分钟以后)
At 3 p.m.: 我们下午三点在公园见面。