Tôi cộng tiền.

• Tôi = I
• cộng = add, add up, or sum
• tiền = money

So the sentence is literally something like I add up money or I total the money.

It is understandable, but it may sound a bit limited or context-specific.

• cộng is most naturally used for mathematical addition
• So cộng tiền usually suggests adding up an amount of money, like totaling numbers

Depending on what you mean, Vietnamese speakers might more often say:

• Tôi tính tiền. = I calculate the amount / I work out the bill
• Tôi đếm tiền. = I count money
• Tôi cộng số tiền lại. = I add up the amount of money

So Tôi cộng tiền. is possible, but it is not always the most natural everyday choice.

Vietnamese does not use articles like English does.

So:

• tiền can mean money, the money, or some money
• The exact meaning depends on context

This is very normal in Vietnamese. Many nouns appear without any article at all.

Vietnamese verbs usually do not change form for tense.

So cộng stays cộng whether the action is present, past, or future. Time is usually understood from context or shown with extra time words, for example:

• Tôi đang cộng tiền. = I am adding up the money
• Tôi đã cộng tiền. = I added up the money
• Tôi sẽ cộng tiền. = I will add up the money

Without those markers, Tôi cộng tiền. is a neutral statement like I add up money or I’m adding up the money, depending on context.

Yes. Tôi is just one way to say I.

It is fairly neutral and polite, so it is a common dictionary-style subject pronoun. But Vietnamese pronouns depend a lot on relationship, age, and situation.

Other possible words for I include:

• mình
• em
• anh
• chị
• con
• cháu
• tớ

So in real conversation, the most natural pronoun may not be tôi. Still, tôi is a very useful default form for learners.

A rough guide for English speakers:

• Tôi ≈ toy
• cộng ≈ something like kohng with a heavy, low tone
• tiền ≈ roughly tyeen with a falling tone

The tones are important:

• tôi: level tone
• cộng: heavy nặng tone
• tiền: falling huyền tone

A rough full pronunciation might be:

• toy kohng tyeen

But that is only approximate. Vietnamese vowels and tones do not match English exactly, so listening to native audio is very important.

Cộng has a few related uses.

As a verb, it means:

• to add
• to add up
• to total

As a mathematical word, it can also correspond to plus.

For example:

• Hai cộng ba bằng năm. = Two plus three equals five.

In Tôi cộng tiền, cộng is a verb, not a conjunction. It means the speaker is doing addition with money amounts.

Vietnamese basic word order is usually:

• Subject + Verb + Object

So:

• Tôi = subject
• cộng = verb
• tiền = object

This is similar to English word order in many simple sentences:

• I add money
• Tôi cộng tiền

That makes this sentence structurally straightforward for English speakers.

No. Tiền does not need a classifier in this sentence.

Classifiers are used in Vietnamese mainly when a noun is counted or specified in certain ways. For example, with physical objects you often need one. But with a mass noun like tiền in a general sense, no classifier is needed here.

If you wanted to talk about specific units of money, then other words might appear, such as:

• một tờ tiền = one banknote
• một đồng = one đồng / one unit of currency
• một ít tiền = a little money

But in Tôi cộng tiền, plain tiền is completely normal.

Usually, no.

If you mean counting bills or cash one by one, use:

• Tôi đếm tiền.

If you mean adding amounts together, use:

• Tôi cộng tiền.
• Tôi cộng số tiền lại.

If you mean calculating the bill / total, use:

• Tôi tính tiền.

This is an important distinction:

• đếm tiền = count money
• cộng tiền = add up money amounts
• tính tiền = calculate the cost / total

You can put không before the verb:

• Tôi không cộng tiền. = I do not add up the money.

This is the standard way to negate a simple Vietnamese sentence.

A common yes-no question pattern is to add không at the end:

• Tôi cộng tiền không? = Am I adding up the money? / Do I add up the money?

But in real conversation, a more natural question often changes the subject depending on who is being asked:

• Bạn cộng tiền không? = Do you add up the money?
• Anh cộng tiền à? = Are you adding up the money?

Vietnamese has several ways to ask questions, and the most natural one depends on the situation.

Yes, it can.

A Vietnamese speaker may wonder:

• Are you adding up the amount of money?
• Are you totaling a bill?
• Are you doing arithmetic with money figures?

So while the sentence is grammatically fine, it often feels like it needs context. In natural conversation, people may say more specific things like:

• Tôi đang cộng số tiền khách trả. = I’m adding up the amount the customer paid.
• Tôi tính tổng số tiền. = I’m calculating the total amount of money.
• Tôi đếm tiền mặt. = I’m counting cash.

So the sentence is correct, but not very specific on its own.