Trước khi ra khỏi phòng, tôi phải đóng cửa sổ.

Trước khi means before.

It introduces an action that happens earlier than the main action. In this sentence:

• Trước khi ra khỏi phòng = Before leaving the room
• tôi phải đóng cửa sổ = I have to close the window

So the structure is:

• trước khi + action
• before + action

It is a very common way to connect two actions in Vietnamese.

Both are possible.

Vietnamese often leaves out the subject when it is already clear from context. In this sentence, the main clause already has tôi (I), so the listener naturally understands that the person leaving the room is also I.

So:

• Trước khi ra khỏi phòng, tôi phải đóng cửa sổ.
• Trước khi tôi ra khỏi phòng, tôi phải đóng cửa sổ.

Both are grammatical.

The version without the repeated tôi sounds more natural and less repetitive in everyday Vietnamese.

Ra khỏi means go out of, leave, or exit from.

It is made of:

• ra = out
• khỏi = away from / out of / off

Together, ra khỏi phòng means leave the room or more literally go out of the room.

So:

• ra khỏi nhà = leave the house
• ra khỏi xe = get out of the vehicle
• ra khỏi phòng = leave the room

They work together to express movement out of a place.

• ra gives the idea of movement outward
• khỏi emphasizes separation from a place

So ra khỏi phòng sounds natural for leave the room / go out of the room.

In some contexts, Vietnamese can use just one element, but ra khỏi is a very common and clear combination for exiting a place.

Yes. Rời khỏi phòng also means leave the room.

The difference is mostly in style:

• ra khỏi phòng = very common, natural, everyday
• rời khỏi phòng = also common, but a bit more formal or written in tone

So both are correct, but ra khỏi phòng feels especially natural in ordinary conversation.

Here, phải means must or have to.

It expresses obligation or necessity:

• tôi phải đóng cửa sổ = I have to close the window
• bạn phải đi ngay = you must leave now

Be careful: phải can also have other meanings in different contexts, but in this sentence it clearly shows obligation.

Yes. Đóng is the normal verb for close/shut things like:

• đóng cửa = close the door
• đóng cửa sổ = close the window
• đóng nắp = close the lid

It is the opposite of mở:

• mở cửa sổ = open the window
• đóng cửa sổ = close the window

So đóng is a very useful general verb for shutting something.

Vietnamese nouns usually do not show a/the the way English does.

So cửa sổ can mean:

• a window
• the window
• sometimes windows, depending on context

In this sentence, English naturally translates it as the window, because the situation suggests a specific window in the room.

If you wanted to be more explicit in Vietnamese, you could say:

• cái cửa sổ = the window / a window
• những cửa sổ = windows
• cửa sổ đó = that window

But in many everyday sentences, just cửa sổ is enough.

Because Vietnamese does not build this structure the same way English does.

In English, we say:

• I have to close the window

In Vietnamese, the pattern is simply:

• tôi phải đóng cửa sổ

So after phải, you directly put the verb:

• phải đi = have to go
• phải học = have to study
• phải đóng cửa sổ = have to close the window

There is no separate word equivalent to English to here.

Yes, absolutely.

Both are natural:

• Trước khi ra khỏi phòng, tôi phải đóng cửa sổ.
• Tôi phải đóng cửa sổ trước khi ra khỏi phòng.

The meaning is the same.

The difference is mostly focus:

• starting with Trước khi... emphasizes the time relationship first
• starting with Tôi phải... emphasizes the obligation first

Both word orders are common in Vietnamese.

The comma separates the introductory time clause from the main clause.

• Trước khi ra khỏi phòng = introductory clause
• tôi phải đóng cửa sổ = main clause

So the comma helps readability, much like in English:

• Before leaving the room, I have to close the window.

If the time clause comes at the end, the comma is often unnecessary:

• Tôi phải đóng cửa sổ trước khi ra khỏi phòng.

No classifier is necessary here.

Vietnamese classifiers are used in certain situations, especially when counting or specifying nouns, but after a preposition-like expression such as ra khỏi, the noun often appears directly:

• ra khỏi phòng = leave the room
• vào nhà = enter the house
• ra khỏi trường = leave school

You could add something like căn phòng in some contexts, but it is not needed here and would usually sound heavier.

No. Tôi means I, but Vietnamese pronouns change depending on relationship, age, formality, and context.

For example:

• tôi phải đóng cửa sổ = I have to close the window
• mình phải đóng cửa sổ = I/we have to close the window (more informal, depends on context)
• con phải đóng cửa sổ = I have to close the window (said by a child)
• em phải đóng cửa sổ = I have to close the window (younger person speaking)

So tôi is a neutral, common, and safe dictionary-style choice.

It is understandable, but usually ra khỏi phòng is more natural here.

Vietnamese often omits đi when the movement meaning is already clear:

• ra khỏi phòng = leave the room
• đi ra khỏi phòng = go out of the room

Adding đi is not always wrong, but it can sound less smooth or a bit unnecessary in this sentence. Native speakers would normally say ra khỏi phòng.

The tones matter a lot. Here is a simple breakdown:

• trước — falling/glottalized tone
• khi — level tone
• ra — level tone
• khỏi — rising-then-broken tone
• phòng — falling tone
• tôi — level-ish diphthong
• phải — rising-then-broken tone
• đóng — rising tone
• cửa — falling/glottalized tone
• sổ — rising-then-broken tone

A useful strategy is to practice in chunks:

• Trước khi ra khỏi phòng
• tôi phải đóng cửa sổ

Then say the whole sentence smoothly.

If your tones are weak, learners often get understood better by keeping the word order correct and speaking slowly, but accurate tones will still help a lot.