Hãy khởi động trước khi chạy.

Hãy marks an instruction, encouragement, or polite command. In Hãy khởi động trước khi chạy, it gives the sense of Do warm up before running or Please warm up before running.

A few useful points:

• It is common in written instructions, advice, slogans, and textbook examples.
• In everyday speech, Vietnamese often drops hãy and just says Khởi động trước khi chạy.
• So hãy adds an imperative feeling, but it is not the main verb.

Here, khởi động means to warm up before exercise.

This expression can also mean to start up in other contexts, such as:

• khởi động xe = start the vehicle
• khởi động máy = start the machine
• khởi động chương trình = launch a program

But in a sentence with chạy, the natural meaning is the exercise-related one: warm up.

It is written as two separate syllables: khởi động. Vietnamese usually writes syllables separately, even when they function together as a single lexical unit.

So for learning purposes, it is best to think of khởi động as one expression meaning:

• to warm up
• or in other contexts, to start up

Do not assume that each written space works the same way as in English.

Trước khi means before in the sense of before doing something.

Structure:

• trước khi + clause/verb phrase

So:

• trước khi chạy = before running

This is a very common pattern in Vietnamese:

• trước khi ăn = before eating
• trước khi ngủ = before sleeping
• trước khi đi học = before going to school

Chạy by itself can mean run. In context, that is enough.

However, chạy has several meanings depending on context, including:

• to run
• to operate
• to move quickly
• to drive off / keep going
• in some contexts, even figurative meanings

If you want to be very explicit that you mean running as exercise, you can say chạy bộ.

So both are possible:

• Hãy khởi động trước khi chạy.
• Hãy khởi động trước khi chạy bộ.

The second is more specific.

Literally, khởi động can sometimes mean start up, but in this sentence that would sound unnatural in English.

Because the sentence includes chạy and sounds like exercise advice, the correct interpretation is:

• Warm up before running

So this is a good example of context deciding the best translation.

Vietnamese often leaves out the subject when it is obvious from context, especially in commands and instructions.

So Hãy khởi động trước khi chạy naturally means something like:

• You should warm up before running
• Warm up before running

There is no need to say you unless the speaker wants to be especially explicit.

Yes. A very natural alternative is:

• Trước khi chạy, hãy khởi động.

This means the same thing.

Both orders are correct:

• Hãy khởi động trước khi chạy.
• Trước khi chạy, hãy khởi động.

The first starts with the action to do. The second starts with the time relationship.

It is grammatical and natural, but it can sound a little formal, instructional, or textbook-like in casual speech.

In everyday conversation, people often say:

• Khởi động trước khi chạy nhé.
• Nhớ khởi động trước khi chạy.
• Nên khởi động trước khi chạy.

These feel more conversational.

So:

• hãy = common in instructions, advice, posters, writing
• omitted or replaced = often more natural in casual speech

A speaker might add particles or use different wording, for example:

• Khởi động trước khi chạy nhé. = Warm up before running, okay?
• Nhớ khởi động trước khi chạy. = Remember to warm up before running.
• Nên khởi động trước khi chạy. = You should warm up before running.

These are often more natural in speech than using hãy.

Each syllable has its own tone. That is important in Vietnamese.

• hãy = hỏi tone
• khởi = hỏi tone
• động = nặng tone
• trước = sắc tone
• khi = level tone
• chạy = nặng tone

For English speakers, the biggest lesson is that tones belong to each syllable, not the whole sentence. If you change the tone, you may change the word.

Yes, Vietnamese often allows a reduced clause or verb phrase after trước khi when the subject is understood.

So trước khi chạy is perfectly natural and means:

• before running
• literally, before [you/someone] run(s) depending on context

Vietnamese does not need a form like English running. The bare verb chạy works here.

Yes, sometimes. For example:

• Hãy khởi động trước lúc chạy.

This is understandable, but trước khi is the more standard and common way to say before doing something.

So for learners, trước khi + verb is the safest pattern to remember.

A natural Vietnamese version would be:

• Đừng chạy mà không khởi động trước.

Or more simply:

• Đừng chạy khi chưa khởi động.

These are useful because they show another common way Vietnamese gives advice or warnings:

• đừng = do not
• chưa = not yet

In normal usage, this sentence strongly suggests exercise because of khởi động plus chạy.

If you saw khởi động in a technical context, it might mean start up, but with chạy here, learners should understand it as exercise advice:

• Warm up before running

So the sentence is best read as a health or sports instruction.