Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.

Ngày mai means tomorrow, and Vietnamese very often puts time expressions near the beginning of a sentence to set the time frame first.

So:

• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.
• literally: Tomorrow, we will go by bus to the airport.

This is very natural in Vietnamese. You can also place the time expression later in some cases, but sentence-initial position is especially common.

Chúng tôi means we, but specifically we excluding the listener.

That is an important distinction in Vietnamese:

• chúng tôi = we, but not you
• chúng ta = we including you

So if the speaker is talking to someone who is not going along, chúng tôi is the right choice.

Example:

• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.
  = Tomorrow, we will take the bus to the airport — and the listener is probably not part of the group.

Sẽ is a future marker. It shows that the action will happen in the future.

So:

• sẽ đi = will go

In this sentence, sẽ helps make the future meaning explicit:

• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.

That said, Vietnamese often leaves out sẽ if the time expression already makes the future clear.

For example, this is also natural:

• Ngày mai, chúng tôi đi xe buýt đến sân bay.

Both can mean Tomorrow, we’re going to the airport by bus, but sẽ makes the future sense a bit more clearly marked.

It can be omitted.

Because Ngày mai already tells you the action is in the future, many speakers would say:

• Ngày mai, chúng tôi đi xe buýt đến sân bay.

Adding sẽ is still correct and natural. It just sounds a little more explicitly future-oriented.

A rough comparison:

• Ngày mai, chúng tôi đi xe buýt đến sân bay. = Tomorrow, we’re going by bus to the airport.
• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay. = Tomorrow, we will go by bus to the airport.

Vietnamese commonly expresses transportation with đi + vehicle.

So:

• đi xe buýt = go by bus / take the bus
• đi xe máy = go by motorbike
• đi ô tô = go by car

The verb đi means go, and the vehicle follows it to show the means of travel.

So even though English says take the bus, Vietnamese structures it more like go bus or go by bus.

Because đi is the main verb, and xe buýt tells you the means of transportation.

Structure:

• đi = go
• xe buýt = bus

So:

• đi xe buýt = go by bus

This is a very common Vietnamese pattern:

• đi bộ = go on foot / walk
• đi tàu = go by train
• đi máy bay = go by plane

Đến means to, arrive at, or reach, depending on context.

In this sentence:

• đến sân bay = to the airport

So the phrase:

• đi xe buýt đến sân bay means:
• go by bus to the airport

Here, đến introduces the destination.

Yes, in many cases tới can replace đến.

So this is also natural:

• Ngày mai, chúng tôi sẽ đi xe buýt tới sân bay.

In everyday speech, đến and tới are often interchangeable when talking about going to a place.

Very generally:

• đến is slightly more neutral/common in standard written Vietnamese
• tới is also very common, especially in speech

Both are correct here.

Vietnamese does not use articles like English a, an, and the in the same way.

So:

• sân bay can mean airport or the airport, depending on context.

In this sentence, the context makes it clear that sân bay means the airport.

This is normal in Vietnamese:

• đến trường = go to school
• vào nhà = enter the house/home
• ra sân bay = go out to the airport

Yes. Sân bay is a compound noun meaning airport.

Its parts are:

• sân = yard, ground, open area
• bay = fly

Together, sân bay means airport.

Vietnamese often builds nouns this way, with two smaller words combining into one idea.

Not strictly.

You can write:

• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.
• Ngày mai chúng tôi sẽ đi xe buýt đến sân bay.

Both are correct.

The comma simply helps separate the time expression from the rest of the sentence, especially in writing. In speech, there is often a small pause there.

The sentence follows a very common Vietnamese order:

Time + subject + future marker + verb + means of transport + destination

So:

• Ngày mai = time
• chúng tôi = subject
• sẽ = future marker
• đi = verb
• xe buýt = means of transport
• đến sân bay = destination

That gives:

• Ngày mai, chúng tôi sẽ đi xe buýt đến sân bay.

This order is very natural in Vietnamese.

Yes. Another common pattern uses bằng:

• Ngày mai, chúng tôi sẽ đến sân bay bằng xe buýt.

This also means:

• Tomorrow, we will go to the airport by bus.

Compare the two:

1. chúng tôi sẽ đi xe buýt đến sân bay
   = literally we will go by bus to the airport

2. chúng tôi sẽ đến sân bay bằng xe buýt
   = literally we will arrive at the airport by bus

Both are natural. The original sentence with đi xe buýt is very common and straightforward.

A more casual spoken version might omit sẽ:

• Ngày mai, chúng tôi đi xe buýt đến sân bay.

If the group includes the listener, you might also change the pronoun:

• Ngày mai, chúng ta đi xe buýt đến sân bay.

So the exact sentence changes depending on:

• whether the listener is included
• how formal or explicit you want to be about the future

The original sentence is completely correct and natural, especially in clear, standard Vietnamese.