Nhân viên chào khách.

The word order is:

subject + verb + object

So here:

• nhân viên = the employee / staff member
• chào = greets / says hello to
• khách = customer / guest

That means Vietnamese is working very similarly to English here:

• The employee greets the customer.

By itself, nhân viên does not clearly show singular or plural.

So it could mean:

• an employee
• the employee
• employees
• the staff

You understand the exact number from context.

If Vietnamese wants to be clearer, it can add words such as:

• một nhân viên = one employee
• các nhân viên = employees
• những nhân viên = some employees / the employees

In your sentence, nhân viên chào khách could describe:

• one employee greeting a customer
• staff greeting customers in general

Vietnamese usually does not use articles like English a / an / the.

So nhân viên can mean:

• an employee
• the employee
• just employee/staff as a general role

And khách can mean:

• a customer
• the customer
• customers
• guests

This is very normal in Vietnamese. You rely on the situation to know which English article makes sense.

Chào means to greet, to say hello to, or to salute politely.

In this sentence, chào khách means:

• greet the customer
• say hello to the customer

It is a very common and important verb in Vietnamese.

For example:

• Chào anh. = Hello.
• Chào khách. = Greet the customer / say hello to the customer.

Because in Vietnamese, chào can take its object directly.

English says:

• greet the customer
• say hello to the customer

Vietnamese uses the simpler pattern:

• chào khách

So khách is the direct object of chào.
You do not need a separate word meaning to here.

It can mean either, depending on context.

Khách is a broad word that can refer to:

• a guest
• a visitor
• a customer
• a client, in some situations

In a business setting, nhân viên chào khách is very naturally understood as:

• The staff greet the customer(s).

In a home or hospitality setting, it could lean more toward:

• The staff greet the guest(s).

Vietnamese verbs do not change form for tense the way English verbs do.

So chào stays chào.

Without extra context, Nhân viên chào khách could mean things like:

• The employee greets the customer.
• The employee is greeting the customer.
• Employees greet customers.

Context tells you the time meaning.

If you want to make time clearer, Vietnamese can add time words or markers, for example:

• Nhân viên đang chào khách. = The employee is greeting the customer.
• Hôm qua, nhân viên chào khách. = Yesterday, the employee greeted the customer.

Yes. It is a correct and natural simple sentence.

It sounds a bit like a basic example sentence or a general statement, which is probably why you are seeing it in learning material.

Depending on context, Vietnamese speakers might also say more specific versions, such as:

• Nhân viên đang chào khách. = The employee is greeting the customer.
• Nhân viên chào khách hàng. = The staff greet the customers.
• Nhân viên ra chào khách. = The employee comes out to greet the customer.

But Nhân viên chào khách is perfectly fine.

No, not in this sentence as it stands.

Vietnamese classifiers are usually needed when you are counting or specifying a noun more exactly, for example:

• một nhân viên = one employee
• một vị khách = one guest/customer (more formal/polite)

But in a simple statement like Nhân viên chào khách, classifiers are not required.

A rough pronunciation guide:

• nhân viên ≈ nyun vee-en
• chào ≈ a bit like jow with a falling tone
• khách ≈ roughly khack with a sharp ending

A few useful notes:

• nh sounds somewhat like the ny in canyon
• ch in southern speech may sound a little like j to English ears, while in northern speech it is closer to a firm ch
• kh is a breathy sound, like a stronger k with air
• tones matter:
  • chào has a falling tone
  • khách has a rising/sharp tone

Exact pronunciation varies by region, so listening to native audio is very helpful.

Usually, just nhân viên is enough and sounds more natural here.

Người can mean person, and sometimes it appears before a noun to emphasize the person, but in this sentence it would usually be unnecessary.

So:

• Nhân viên chào khách. = natural
• Người nhân viên chào khách. = possible in some contexts, but less neutral and not the usual basic phrasing

For a simple statement, stick with nhân viên.

You can add plural markers if needed:

• Các nhân viên chào khách.
• Các nhân viên chào các khách hàng.

A few notes:

• các clearly marks plural
• khách hàng is a more specific word for customer
• often Vietnamese still leaves number unmarked if the context is clear

So in real life, even Nhân viên chào khách can already imply a general plural idea like staff greet customers.