Learn Hardcore Japanese: kanozyo ha hutuu ha sizuka da ga, kaigi de ha kanari hanasu. - She’s usually quiet, but she talks quite a lot in meetings.

The first は in 彼女は sets the main topic: “as for her.”
The second は in 普通は is a contrastive/time-frame は: “as for normal times/usually.” It’s common to stack a main topic and a contrastive frame like time or place: “As for her, as for usual times, …”

What is the が doing after だ in 静かだが?

Here が is a conjunction meaning “but/however,” not the subject marker. With a noun or a na-adjective you need だ before the conjunctive が:

Noun/na-adj: 学生だが… / 静かだが…
i-adj/verb: 寒いが… / 行くが… (no だ needed)

Is だが too formal? What are natural alternatives?

Neutral/written: …静かだが、…
Casual: …静かだけど、… or …静かだけどね、…
Polite: …静かですが、…
Sentence-initial “however”: しかし、… / でも、… Choose based on register and setting; だが feels more written or matter-of-fact.

Why 会議で and not 会議に?

で marks the place where an action happens (location of action): 会議で話す = “speak in/at a meeting.”
に marks destination, time, or target: 会議に行く / 会議に参加する.
So 会議には話す is unnatural because 話す doesn’t take に for location.

What does the extra は in 会議では do? How is that different from just 会議で?

会議では uses a contrastive は: “as for in meetings (as opposed to other contexts).”

会議でかなり話す = neutral location (“at meetings she talks a lot”).
会議ではかなり話す = highlights the contrast with other situations.

What’s the difference between 普通は, 普段は, and 普通に?

普通は: “normally/as a rule.” Broad, rule-of-thumb feel.
普段は: “usually in day-to-day life.” Emphasizes habitual everyday state; very natural here.
普通に: literally “in a normal way,” but in colloquial speech it often means “pretty/quite.”
Beware: 普通に静かだ can be heard as “pretty quiet,” not “quiet under normal circumstances.” If you mean “usually,” use 普通は or 普段は.

Why is 話す in plain nonpast? Is that a tense choice?

Nonpast plain form expresses habitual/general tendencies. The sentence describes her typical behavior. If you want a polite tone, use the です/ます style throughout:

Plain: 静かだが、(会議では)かなり話す。
Polite: 静かですが、(会議では)かなり話します。 Keep the style consistent, especially in writing.

Can I say 静かなが? How do I connect 静か to “but”?

No. For na-adjectives and nouns:

Use だが (written) or だけど (casual): 静かだが / 静かだけど
If you use のに (see below), use 静かなのに (because のに needs な after na-adjectives).
For i-adjectives: 静か is not i-adj; but e.g., 忙しいが / 忙しいけど.

What nuance does かなり have? Could I use よく, たくさん, or 結構 instead?

かなり: “considerably/quite a lot,” relatively objective-sounding degree.
よく話す: can mean “talks often” or “talks a lot” (frequency vs amount; slightly ambiguous).
たくさん話す: emphasizes quantity/amount (“talks a lot”).
結構話す: “quite a bit,” casual; can be similar to かなり but more colloquial.
More formal: 相当, だいぶ (context-dependent). Avoid とても話す; とても usually modifies adjectives/adverbs, not verbs of action like this.

Can I use しゃべる, 話をする, or 発言する instead of 話す?

しゃべる: “chatter/speak” (more casual, sometimes sounds chatty).
話をする: “to talk/to have a talk,” neutral, a bit roundabout.
発言する: “make remarks/speak up” in a meeting; more formal/professional.
Choose based on tone and what you want to emphasize:
会議ではかなり発言する sounds businesslike.
会議ではよくしゃべる sounds more casual/colloquial.

Why 彼女は and not 彼女が?

は sets a known topic (“as for her”). が marks the grammatical subject and often introduces or highlights new/contrastive information.
彼女が普通は静かだ would read like “It’s she who is usually quiet (as opposed to others),” which is not the neutral setup you want here. 彼女は is the natural topic choice.

Is 彼女 natural here? Doesn’t it also mean “girlfriend”?

彼女 can mean “she” or “girlfriend.” In real conversations, Japanese often avoid third-person pronouns and use names or roles instead (or just omit the subject if clear). Depending on context, you might say:

山田さんは普段は静かだが、会議ではかなり話す。
Or simply drop it if already understood: 普段は静かだが、会議ではかなり話す。

What about the spacing and pronunciation of particles?

Standard Japanese writing doesn’t use spaces between words; the spaces here are for learners.
Particle は is pronounced “wa,” so 彼女は = “kanojo wa.”
では is “dewa,” often contracted to じゃ in casual speech: 会議じゃかなり話す.

Can I change the word order, like 会議では、彼女はかなり話す?

Yes. Word order is flexible as long as particles mark roles. Fronting 会議では emphasizes the meeting context:

会議では、彼女はかなり話す。 You can also split into two sentences for emphasis:
彼女は普段は静かだ。会議ではかなり話す。

Could I use のに instead of が for “but”?

Yes, but it adds an “unexpected/despite that” nuance:

普段は静かなのに、会議ではかなり話す。 = “She’s usually quiet, yet (surprisingly) she talks a lot in meetings.” が/けど is a neutral contrast; のに implies the second part is contrary to what you’d expect from the first.