yeohaeng gaseo yeppeun yeopseoreul saseo upyodo gati sasseo.

In Korean, 여행 가다 is a very common expression meaning to go on a trip or to travel. Here, 여행 often behaves like part of a fixed phrase, so speakers very often leave out 을/를.

• 여행 가다 = to go travel / to go on a trip
• 여행을 가다 is not the usual everyday form

So 여행 가서 sounds natural and conversational.

가서 is the connective form of 가다 (to go).

• 가다 → 가서

The ending -아서/어서 often links actions together, like:

• go and...
• after going...
• while there...

So 여행 가서 gives the idea of:

• going on a trip and then...
• while on the trip...

In this sentence, it connects the trip to the next action naturally.

Here, it mainly connects actions in sequence.

So:

• 여행 가서 예쁜 엽서를 사서...

means something like:

• I went on a trip, bought a pretty postcard, and...

Sometimes -아서/어서 can mean because, but in this sentence it is best understood as a smooth chain of events.

The verb 사다 means to buy.

In the sentence, it appears as:

• 사서 = buy and / after buying
• 샀어 = bought

So the sentence chains actions like this:

1. 여행 가서 = went on a trip
2. 예쁜 엽서를 사서 = bought a pretty postcard
3. 우표도 같이 샀어 = also bought stamps

Using -서 repeatedly is normal in Korean when listing connected actions.

예쁘다 is a descriptive verb meaning to be pretty.
When Korean descriptive verbs directly modify a noun, they usually change into a noun-modifying form.

• 예쁘다 → 예쁜
• 예쁜 엽서 = a pretty postcard

So 예쁜 is the correct adjective-like form before a noun.

엽서 means postcard.

So:

• 예쁜 엽서 = a pretty postcard

This is a useful travel-related word in Korean.

The particle 도 means also / too.
When 도 is used, it usually replaces other particles like 은/는, 이/가, or 을/를.

So:

• 우표를 샀어 = bought stamps
• 우표도 샀어 = bought stamps too / also bought stamps

You do not normally say 우표를도.

같이 usually means together, but in sentences like this it can also mean along with that or at the same time.

So 우표도 같이 샀어 means something like:

• I bought stamps too
• I bought stamps along with it as well

It does not necessarily mean the speaker bought them with another person. It just means the stamps were bought together with the postcard.

샀어 is casual informal speech.

It comes from:

• 사다 = to buy
• 샀어 = bought

This is the kind of form you would use with:

• close friends
• younger people
• someone you speak casually with

A more polite version would be:

• 샀어요

So the full polite sentence would be:

• 여행 가서 예쁜 엽서를 사서 우표도 같이 샀어요.

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

So even though the sentence does not say I, it is naturally understood as something like:

• I went on a trip, bought a pretty postcard, and bought stamps too.

This omission is very common in Korean and sounds natural, not incomplete.

It strongly suggests that, but it does not state it explicitly.

Because the actions are connected so naturally:

• bought a postcard
• also bought stamps

many listeners would assume the stamps were for mailing the postcard.
But grammatically, the sentence only says that both were bought.

Yes, that is a very natural translation.

Because 여행 가서 can feel like:

• after going on a trip
• while on a trip
• when I went traveling

All of these can work depending on context. Korean often leaves that relationship a little flexible, and English chooses the smoothest wording.

Yes. In Korean, when several actions are linked together, the earlier verbs often take connector forms like -서, and the final verb carries the tense and sentence ending.

So here:

• 가서 = connector
• 사서 = connector
• 샀어 = final verb, past tense, casual ending

That final verb is what completes the sentence.