Sau khi làm xong việc ở văn phòng, chị tôi sẽ đi bộ về nhà.

Sau khi means after and introduces a time clause.

So:

• Sau khi làm xong việc ở văn phòng = After finishing work at the office

A very common pattern in Vietnamese is:

• sau khi + verb phrase, main clause
• before/after doing X, ...

Unlike English, Vietnamese does not need a separate subject inside that first clause if it is understood from context.

Làm means to do/work, and xong means finished / completed.

Together, làm xong means:

• finish doing
• do something completely

This is a very common Vietnamese pattern:

• verb + xong = finish verb-ing

Examples:

• ăn xong = finish eating
• viết xong = finish writing
• học xong = finish studying

So làm xong việc means finish the work.

Vietnamese often leaves out the subject when it is obvious from context.

In this sentence:

• Sau khi làm xong việc ở văn phòng, chị tôi sẽ đi bộ về nhà.

the understood subject of làm xong is the same as the subject of the main clause, chị tôi.

So the meaning is:

• After my older sister finishes her work at the office, she will walk home.

Vietnamese avoids repeating subjects when they are already clear.

Việc means work, task, or job, depending on context.

Here, làm xong việc most naturally means:

• finish the work
• be done with work

So việc here is not necessarily one specific task; it can refer more generally to the work she has to do.

A useful comparison:

• công việc = work/job, often a bit more formal or broader
• việc = work/task, very common in everyday speech

Ở means at / in for location.

So:

• văn phòng = office
• ở văn phòng = at the office / in the office

In this sentence, ở văn phòng tells us where the work is being done.

So:

• làm xong việc ở văn phòng = finish the work at the office

Depending on context, this can mean:

1. finish work that is done at the office, or
2. finish working while at the office

Both are natural interpretations.

Vietnamese family words are very specific about age and relationship.

• chị = older sister
• em = younger sibling
• anh = older brother

So chị tôi literally means:

• older sister of me
• natural English: my older sister

Vietnamese normally puts the family noun first and the possessor after it:

• chị tôi = my older sister
• mẹ tôi = my mother
• bạn tôi = my friend

This is the normal Vietnamese word order.

Sẽ marks future time, similar to will in English.

So:

• chị tôi sẽ đi bộ về nhà = my older sister will walk home

Important point: Vietnamese does not always have to mark tense. Often time is understood from context. But sẽ is used when the speaker wants to clearly show that something is in the future.

Break it down like this:

• đi = go
• bộ = on foot
• đi bộ = walk
• về = return/go back
• nhà = home/house
• về nhà = go home / return home

So:

• đi bộ về nhà = walk home

A useful way to think about it is:

• đi bộ tells how
• về nhà tells where to

Về often means to return, back to, or toward home/a place of return.

So:

• về nhà = go home / return home

This is different from simply going to a place in general. For example:

• đi đến trường = go to school
• về nhà = go back home

In many everyday situations, về strongly suggests returning to a familiar place.

Yes, it could, depending on context.

• Sau khi làm xong việc ở văn phòng, chị tôi đi bộ về nhà.

This could mean:

• she walks home after work (habitually), or
• she walks home after finishing work, if the time is clear from context

Adding sẽ makes the future meaning more explicit:

• chị tôi sẽ đi bộ về nhà = she will walk home

So sẽ is not always required, but it helps clarify the time.

Yes. The overall structure is very typical:

• Time clause
  • main clause

So:

• Sau khi làm xong việc ở văn phòng = after finishing work at the office
• chị tôi sẽ đi bộ về nhà = my older sister will walk home

A common Vietnamese pattern is:

• [time/background information], [main action]

This is very natural in Vietnamese and often sounds smoother than starting directly with the subject.

Sometimes, but not in exactly the same way.

• sau khi + verb phrase = after doing something
• sau + noun/time expression = after/later than something

Examples:

• sau khi ăn xong = after finishing eating
• sau bữa ăn = after the meal
• sau đó = after that

So in this sentence, sau khi is the correct choice because it introduces an action: làm xong việc.

It is grammatical and natural. It sounds like clear standard Vietnamese.

In casual speech, a speaker might shorten it a little, for example:

• Làm xong việc ở văn phòng, chị tôi sẽ đi bộ về nhà.
• Sau khi làm xong việc, chị tôi sẽ đi bộ về nhà.

These versions drop information that may already be understood.

But the original sentence is perfectly good, especially for learners, because it clearly shows all the parts:

• time relation
• completed action
• location
• future marker
• destination