Thợ máy bơm lốp.

In this sentence, thợ máy is best understood as a single noun phrase meaning mechanic.

• thợ = a skilled worker, craftsman, repair worker
• máy = machine

But when combined as thợ máy, it does not simply mean worker machine. It functions as a set expression for a person who works with machines, especially a mechanic.

So the sentence structure is:

• thợ máy = subject
• bơm = verb
• lốp = object

The verb is bơm.

It means to pump or inflate. In this sentence, bơm lốp means pump a tire / inflate a tire.

So the sentence is built very simply:

• thợ máy = the mechanic
• bơm = pumps / is pumping
• lốp = tire

This is a normal Vietnamese subject–verb–object pattern.

Vietnamese usually does not require articles the way English does.

So thợ máy can mean:

• a mechanic
• the mechanic
• sometimes just mechanics in a very general sense

The exact meaning depends on context.

Likewise, lốp can mean:

• a tire
• the tire
• tires, if the situation makes that clear

Vietnamese often leaves this information unstated unless it needs to be specific.

By itself, this sentence does not mark tense.

Vietnamese often leaves tense unstated when the time is understood from context. So Thợ máy bơm lốp could mean:

• The mechanic pumps the tire
• The mechanic is pumping the tire
• in some contexts, even The mechanic pumped the tire

If you want to be more explicit, Vietnamese can add time words or aspect markers, for example:

• đang for an action in progress
• đã for a completed past action
• sẽ for future

Examples:

• Thợ máy đang bơm lốp. = The mechanic is pumping the tire.
• Thợ máy đã bơm lốp. = The mechanic pumped the tire.
• Thợ máy sẽ bơm lốp. = The mechanic will pump the tire.

Lốp usually refers to the tire.

In everyday usage, bơm lốp is understood as inflating the tire, even though physically the air goes into the inner tube or air chamber. This is similar to how English speakers say pump a tire.

Depending on context, you may also hear related words such as:

• bánh xe = wheel
• lốp xe = vehicle tire
• ruột xe = inner tube

But in a simple sentence like this, lốp is completely natural.

It is not a single fixed word, but it is a very common and natural verb + object combination.

• bơm = pump / inflate
• lốp = tire

So bơm lốp literally means pump the tire or inflate the tire.

Vietnamese often forms actions this way:

• rửa xe = wash the vehicle
• sửa máy = repair the machine
• vá lốp = patch the tire
• bơm lốp = inflate the tire

So this pattern is very common and useful.

The tones are important here:

• thợ — nặng tone
• máy — sắc tone
• bơm — ngang tone
• lốp — sắc tone

A rough guide:

• thợ: low, short, and heavy/glottalized
• máy: rising
• bơm: level
• lốp: rising

So you should not pronounce all four words with flat English-style intonation. The tones help distinguish meaning.

This is the normal order.

Vietnamese usually follows:

subject + verb + object

So:

• thợ máy = subject
• bơm = verb
• lốp = object

If you change the order, you usually change the meaning or make the sentence unnatural.

For example, Bơm lốp thợ máy would not be a normal way to say the same thing.

Vietnamese can use a bare noun phrase as the subject, especially in simple statements.

So thợ máy alone is enough to mean the mechanic / a mechanic. You do not need a pronoun like he unless the speaker wants one.

You also do not need a classifier here because classifiers are mainly used with numbers, demonstratives, or when a noun is being specifically counted or pointed out.

For example:

• một người thợ máy = a mechanic
• người thợ máy đó = that mechanic

But in Thợ máy bơm lốp, the simpler noun phrase is fine.

Yes, it is grammatical and understandable, especially as a short textbook-style sentence.

In real conversation, a speaker might make it more specific depending on context, for example:

• Người thợ máy đang bơm lốp.
• Anh thợ máy bơm lốp xe.
• Thợ máy đang bơm lốp xe.

These versions can sound a little more natural in everyday speech because they add:

• đang for ongoing action
• xe to specify vehicle tire
• anh or người to make the subject more concrete

But the original sentence is still a perfectly valid basic Vietnamese sentence.