Tôi làm việc cả đêm.

Tôi means I.

It is a neutral, polite pronoun, and it is very common in textbook Vietnamese. In real conversation, Vietnamese often uses kinship-style pronouns instead, depending on age and relationship, such as mình, anh, em, chị, etc.

So Tôi làm việc cả đêm is correct and natural, but it can sound a bit neutral or formal compared with everyday casual speech.

Làm việc means to work.

• làm by itself is a very broad verb meaning do, make, or sometimes work
• làm việc more specifically means to work, especially in the sense of doing one’s job or laboring

So:

• Tôi làm việc cả đêm = I worked / work all night
• Tôi làm cả đêm is also possible, but it can sound a little broader, like I was doing things all night depending on context

If you want the clear meaning work, làm việc is a safe choice.

Cả đêm means the whole night or all night.

Here, cả adds the idea of the entire duration.
So cả đêm = all night long.

In this sentence, it tells you how long the action lasted:

• Tôi làm việc cả đêm = I worked all night

Vietnamese often expresses duration without a separate word equivalent to English for.

In English, we say:

• I worked all night
• I worked for the whole night

Vietnamese simply uses the time phrase directly after the verb:

• làm việc cả đêm

That is very normal Vietnamese sentence structure.

By itself, it does not mark tense clearly.

Vietnamese usually relies on context, time words, or aspect markers rather than changing the verb form. So Tôi làm việc cả đêm could mean different things depending on context:

• I work all night
• I worked all night
• I will work all night

If you want to make it clearer, you can add time or aspect words:

• Tôi đã làm việc cả đêm. = I worked all night
• Tôi đang làm việc cả đêm. = I am working all night / I’ve been working all night depending on context
• Tôi sẽ làm việc cả đêm. = I will work all night

That is the normal basic Vietnamese order:

subject + verb + time/duration expression

So:

• Tôi = subject
• làm việc = verb
• cả đêm = duration/time phrase

This is very similar to English in this case, which makes the sentence relatively easy to understand for English speakers.

Yes, you can.

Tôi làm cả đêm is grammatical and natural. It usually means I worked all night or I was busy doing something all night.

The difference is:

• Tôi làm việc cả đêm = more clearly I worked all night
• Tôi làm cả đêm = can be slightly broader, depending on context

So if you want to emphasize actual work or employment-related activity, làm việc is more precise.

They are very close, and both can often be translated as all night.

• cả đêm = the whole night
• suốt đêm = throughout the night

In many situations, they are interchangeable:

• Tôi làm việc cả đêm.
• Tôi làm việc suốt đêm.

Both are natural.
Suốt đêm can sometimes feel a little more like emphasizing uninterrupted duration.

A rough pronunciation guide is:

• tôi – like toy but with a Vietnamese vowel quality
• làm – roughly like lahm
• việc – roughly vee-uhk, with a short, clipped ending
• cả – roughly gah with a rising-broken tone
• đêm – roughly dem with the Vietnamese đ sound, which is like a regular English d

The tones matter a lot:

• tôi – level-ish tone
• làm – low falling
• việc – low/heavy tone
• cả – dipping/rising broken tone
• đêm – level tone

If you are learning pronunciation, việc and cả are often the trickiest parts.

It is neutral and correct.

Because it uses tôi, it can sound a bit more formal, careful, or neutral than what close friends might say in daily conversation. In casual speech, a speaker might change the pronoun depending on who they are talking to:

• Anh làm việc cả đêm.
• Em làm việc cả đêm.
• Mình làm việc cả đêm.

So the sentence itself is not overly formal, but tôi gives it a slightly textbook-like or polite feel.

Yes, that is a very natural interpretation.

Even though the literal structure is simply I work all night, in real usage it often implies that the person spent the whole night working, possibly without sleeping.

If you wanted to make that idea even more explicit, you could say something like:

• Tôi thức cả đêm để làm việc. = I stayed up all night to work
• Tôi làm việc suốt đêm không ngủ. = I worked all night without sleeping

But the original sentence already strongly suggests that idea in many contexts.