qǐng bǎochí lěngjìng.

请 here means please. It makes the sentence more polite.

So the pattern is:

请 + verb phrase

In this case:

请保持冷静。 = Please remain calm.

A useful point: 请 does not always map perfectly to English please in every situation, but in commands and requests like this, that is the most natural translation.

In Chinese, the subject is often omitted when it is obvious from context.

So 请保持冷静。 naturally means:

• Please remain calm
• Please keep calm

The listener is understood, so you do not need to say 你.

If you want to make it explicit, you can say:

请你保持冷静。

That still means Please remain calm, but it sounds a little more direct because the person is specifically named as the one being addressed.

保持 means to keep, to maintain, or to remain in a certain state.

In this sentence:

• 保持 = keep / maintain
• 冷静 = calm

So together:

保持冷静 = keep calm / remain calm

You will often see 保持 used before a state or condition, for example:

• 保持安静 = keep quiet
• 保持距离 = keep distance
• 保持健康 = stay healthy / maintain good health

冷静 is usually an adjective meaning calm, cool-headed, or composed.

In 保持冷静, it functions as the state being maintained:

• 保持 = maintain
• 冷静 = calm

So the structure is basically:

verb + state

This is very common in Chinese.

Also, 冷静 can sometimes appear in ways that feel more verb-like in English, but it is best for learners to think of it mainly as an adjective meaning calm.

These two words are different:

• 冷静 = calm, emotionally controlled, level-headed
• 安静 = quiet, not noisy

So:

• 请保持冷静。 = Please stay emotionally calm.
• 请保持安静。 = Please stay quiet.

If someone is panicking, arguing, or getting upset, 冷静 is the right word.

If a teacher wants students not to make noise, 安静 is the right word.

The pinyin is:

qǐng bǎochí lěngjìng

Tones:

• 请 qǐng — 3rd tone
• 保 bǎo — 3rd tone
• 持 chí — 2nd tone
• 冷 lěng — 3rd tone
• 静 jìng — 4th tone

A rough pronunciation guide for English speakers:

• qǐng sounds a bit like cheeng, but with the Chinese q sound
• bǎo sounds a bit like baow
• chí sounds like chir without a strong r
• lěng sounds like lung with a different vowel
• jìng sounds a bit like jeeng

Important: Chinese pronunciation is not fully captured by English spelling, so pinyin plus listening practice is the best approach.

There is no major required tone change here like the famous 3rd tone + 3rd tone rule turning the first one into a rising tone in full speech, but there is still a natural pronunciation adjustment in connected speech.

For example:

• 请 qǐng is 3rd tone
• 保 bǎo is 3rd tone

When two 3rd tones come together, the first one is often pronounced more like a 2nd tone in natural speech.

So 请保... may sound more like:

qíng bǎo...

But learners should still remember the dictionary tones as:

qǐng bǎochí lěngjìng

Also:

• 冷 lěng is 3rd tone
• 静 jìng is 4th tone

That combination stays as written.

It can be either, depending on context and tone of voice.

Because of 请, it is more polite than just saying:

保持冷静。

But in real life, it is still often used in serious situations such as:

• announcements
• warnings
• crowd control
• customer service
• emergencies

So it can sound like a firm but polite instruction:

Please remain calm.

In a casual personal situation, it may sound a little formal or official.

Yes, absolutely.

请保持冷静。 and 请你保持冷静。 are both correct.

The difference is:

• 请保持冷静。 = more general, often used in signs, announcements, or formal speech
• 请你保持冷静。 = clearly directed at one person or group being addressed

Adding 你 can make it feel more personal, and sometimes more pointed.

Because 冷静 here is not simply describing someone with a basic A is B sentence. It is the state that follows the verb 保持.

Compare:

• 他很冷静。 = He is very calm.
• 请保持冷静。 = Please remain calm.

In the first sentence, 冷静 is the main description of the subject, so 很 is commonly used.

In the second sentence, 冷静 comes after 保持, so you do not use 很 there.

Saying 请保持很冷静 would sound unnatural.

Yes, it is somewhat formal or neutral-formal.

It sounds natural in contexts like:

• public announcements
• police or security instructions
• medical settings
• customer service
• written notices

In everyday conversation with a friend, you might hear other expressions too, such as:

• 冷静一点。 = Calm down a bit.
• 别激动。 = Don’t get excited / Don’t get worked up.
• 先冷静一下。 = Calm down first.

So 请保持冷静 is correct and natural, but it has a slightly official tone.

The structure is:

请 + 保持 + adjective/state

More specifically:

• 请 = polite request marker
• 保持 = maintain / keep
• 冷静 = calm

So the sentence pattern is:

Please + maintain + a certain state

You can use the same pattern with other words:

• 请保持安静。 = Please keep quiet.
• 请保持耐心。 = Please remain patient.
• 请保持警惕。 = Please stay alert.

This is a very useful pattern to learn.

Yes. A close word-for-word breakdown is:

• 请 = please
• 保持 = keep / maintain
• 冷静 = calm

So:

请保持冷静。 = Please keep calm.

However, in natural English, Please remain calm is often the most common translation, especially in official or emergency situations.

Both are fine.

Chinese often uses the full stop 。 even for requests, instructions, and commands that might sometimes use an exclamation mark in English.

So 请保持冷静。 with 。 is completely normal.

If you wrote:

请保持冷静！

that would sound more forceful or urgent.

So:

• 。 = neutral, standard, often written style
• ！ = stronger emotion or urgency

Both are possible, depending on the situation.