yīshēng shuō tā de zhèngzhuàng bú tài yánzhòng, kěshì yào duō hē shuǐ.

This is because of a common tone change rule in Mandarin:

• 不 is normally fourth tone: bù
• But when it comes before another fourth-tone syllable, it changes to second tone: bú

So:

• 不太 = bú tài
• not bù tài

This makes the pronunciation flow more naturally.

她的症状 literally means her symptoms.

Breakdown:

• 她 = she / her
• 的 = possessive particle, similar to English 's or of
• 症状 = symptoms

So:

• 她的症状 = her symptoms

In this sentence, 的 links 她 to 症状 and shows possession.

的 is a very common particle used to show possession or modification.

Here:

• 她的症状
• literally: she + de + symptoms
• natural English: her symptoms

You can think of 的 as working like:

• my in my book
• John's in John's friend

More examples:

• 我的医生 = my doctor
• 他的水 = his water
• 老师的名字 = the teacher's name

In this sentence, 的 is just marking her as belonging to or describing symptoms.

Mandarin often follows a subject + verb + statement structure very directly.

Here:

• 医生 = the doctor
• 说 = said
• 她的症状不太严重 = her symptoms are not too serious

So the whole sentence is:

• 医生说她的症状不太严重
• The doctor said that her symptoms are not too serious.

Mandarin usually does not need a separate word for that in this kind of sentence. English often says:

• The doctor said that...

But in Chinese, you can just put the reported statement right after 说.

Here, 说 means said or to say.

• 医生说... = The doctor said...

Even though 说 can sometimes be translated as speak, in this sentence it is clearly introducing reported speech or information, so say/said is the best translation.

Examples:

• 他说中文。 = He speaks Chinese.
• 他说他很忙。 = He said he is very busy.

So the meaning depends on context.

不太严重 means not too serious or not very serious.

Breakdown:

• 不 = not
• 太 = too / very (depending on context)
• 严重 = serious

Together, 不太 + adjective often means:

• not very...
• not too...

So:

• 不太严重 = not very serious / not too serious

This is softer and more natural than simply saying 不严重.

Compare:

• 不严重 = not serious
• 不太严重 = not too serious / not very serious

The second one sounds a bit less absolute.

In this pattern, 太 helps express degree.

On its own, 太 + adjective often means too or very, depending on context:

• 太好了 = great / very good
• 太贵了 = too expensive

But when used as 不太 + adjective, it usually means:

• not very...
• not too...

So:

• 不太严重 = not very serious

This is a very useful pattern:

• 不太舒服 = not very comfortable / not feeling very well
• 不太清楚 = not very clear
• 不太忙 = not too busy

Yes, 可是 means but.

It introduces a contrast:

• her symptoms are not too serious
• but she should drink more water

So:

• 医生说她的症状不太严重，可是要多喝水。

This means something like:

• The doctor said her symptoms are not too serious, but she should drink more water.

A few common Chinese words for but are:

• 可是
• 但是
• 不过

They are often similar in meaning, though 可是 can sound a little more conversational or emphatic.

The subject is understood from context.

The sentence says:

• 医生说她的症状不太严重，可是要多喝水。

After 可是, the subject 她 is omitted because it is already clear that the sentence is still talking about her.

So the full idea is:

• ...可是（她）要多喝水。
• ...but (she) needs to drink more water.

In Mandarin, it is very common to leave out subjects when they are obvious from context.

Here, 要 means need to or should, not want.

That is a very common question because 要 can have several meanings depending on context.

In this sentence:

• 要多喝水 = need to drink more water / should drink more water

Because the sentence is about medical advice, 要 is naturally understood as need to or should.

Compare:

• 我要喝水。 = I want to drink water.
• 你感冒了，要多休息。 = You have a cold; you need to rest more.

So context is very important.

Here, 多 means more, and it comes before the verb to show doing that action to a greater degree.

• 多喝水 = drink more water

Structure:

• 多 + verb
• or more specifically here, 多 + 喝 + 水

This is a common pattern:

• 多吃水果 = eat more fruit
• 多休息 = rest more
• 多运动 = exercise more

In English, more often comes before the noun or later in the phrase, but in Chinese, 多 commonly comes before the verb phrase.

Because 喝水 is a general expression meaning drink water.

In Chinese, when speaking generally about drinking water, you often just say:

• 喝水 = drink water

You do not need a measure word unless you are counting or specifying an amount.

For example:

• 喝水 = drink water
• 喝一杯水 = drink a glass of water
• 喝很多水 = drink a lot of water

In 多喝水, the idea is general advice, so 水 by itself is perfectly natural.

Yes, in natural English it can be translated that way depending on context.

Strictly speaking:

• 症状 = symptoms

So the most literal translation is:

• her symptoms are not too serious

But in English, people sometimes say:

• her condition isn't too serious
• it's not too serious

These can sound more natural in some situations, even if they are a little less literal.

So the Chinese specifically mentions symptoms, but a smoother English translation may vary.

Yes, very common.

This sentence uses several patterns that appear often in medical or everyday health advice:

• A 说 B 不太 + adjective
• 可是/但是 + 要 + verb phrase

So you might hear similar sentences like:

• 医生说我没什么问题，可是要多休息。
  The doctor said there's no major problem, but I need to rest more.

• 医生说不严重，但是要按时吃药。
  The doctor said it's not serious, but I need to take medicine on time.

• 医生说她好多了，可是还要观察。
  The doctor said she is much better, but she still needs observation.

So this sentence is a very natural example of how Mandarin expresses diagnosis plus advice.