gichayeogi gakkaunikka taeksireul bureul piryoga eobsgesseoyo.

This is because 가깝다 is a ㅂ-irregular adjective.

When a ㅂ-irregular stem is followed by a suffix that starts with a vowel, the ㅂ changes to 우.

So:

• 가깝다 → stem: 가깝-
• -으니까 attaches
• ㅂ changes to 우
• 가까우니까

This is the same pattern as:

• 덥다 → 더우니까
• 춥다 → 추우니까
• 어렵다 → 어려우니까

So 가까우니까 is the correct natural form.

-(으)니까 means something like because, since, or as.

In this sentence, it gives the reason for the second part:

• 기차역이 가까우니까 = because the train station is close
• 택시를 부를 필요가 없겠어요 = there probably won’t be any need to call a taxi

So the whole sentence expresses a reason-and-result relationship.

A learner may compare it with -아/어서, which can also mean because. In many situations they are similar, but -(으)니까 often sounds a little more like the speaker is presenting a reason for a judgment, suggestion, or conclusion.

이/가 is the subject marker.

Here, 기차역이 가까우니까 means since the train station is close. The train station is the thing being described as close, so it takes the subject marker:

• 기차역이 = the train station as the subject
• 가깝다 = to be close

A learner might expect 은/는 instead. That is also possible in some contexts:

• 기차역은 가까우니까 ...

But that would add more of a topic/contrast feeling, like as for the train station, since it’s close...

Using 이 here is a straightforward way to present the information.

Yes. 부르다 has several meanings, and one very common one is to call/summon someone or something.

So:

• 택시를 부르다 = to call a taxi
• 사람을 부르다 = to call a person
• 이름을 부르다 = to call someone’s name

In this sentence, it means to call for a taxi, not to ride in a taxi.

So if an English speaker sees 부르다 and only knows it as to sing or to call a name, this is a good reminder that Korean verbs often have multiple related uses.

This is the pattern:

• Verb-(으)ㄹ 필요가 없다 = there is no need to ...

So here:

• 부르다 → 부를
• 필요 = need/necessity
• 필요가 없다 = there is no need

Together:

• 택시를 부를 필요가 없다 = there is no need to call a taxi

This structure is extremely common and useful:

• 갈 필요가 없어요 = There’s no need to go
• 걱정할 필요가 없어요 = There’s no need to worry
• 살 필요가 없어요 = There’s no need to buy it

Because this uses the future/modifying form -(으)ㄹ attached to the verb stem.

For 부르다:

• dictionary form: 부르다
• stem: 부르-
• add -ㄹ because the stem ends in a vowel
• 부를

This form modifies the noun 필요:

• 부를 필요 = the need to call

So 부를 here is not a separate tense by itself in English terms. It is the verb form used before a noun.

-겠- often adds a sense of:

• supposition
• guess
• judgment
• future-oriented conclusion
• sometimes polite softening

So:

• 필요가 없어요 = there is no need
• 필요가 없겠어요 = there probably won’t be a need / I don’t think there will be a need

In this sentence, the speaker is making a reasonable conclusion based on the situation:

• The station is close, so I guess we won’t need to call a taxi.

That is why 없겠어요 sounds very natural.

No. That is a very common learner misunderstanding.

While -겠- can sometimes refer to the future, it often expresses the speaker’s attitude, such as:

• guessing
• assuming
• judging
• intending
• softening

In this sentence, it is not just a plain future marker. It sounds more like:

• I suppose
• it seems
• probably

So 없겠어요 is closer to there probably won’t be any need than a simple mechanical future tense.

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

So 택시를 부를 필요가 없겠어요 could mean:

• I probably won’t need to call a taxi
• we probably won’t need to call a taxi
• you probably won’t need to call a taxi

The exact subject depends on the situation.

That is very normal in Korean. Native speakers often omit subjects when they are already understood.

을/를 is the object marker.

Here, 택시 is the thing being called, so it is the object of 부르다:

• 택시를 부르다 = to call a taxi

This is a standard verb-object pattern.

Yes, literally it is the train station is close, but Korean often leaves out the reference point when it is obvious.

In English, we often want to specify:

• The train station is close to here
• The station is nearby

In Korean, if the context already makes it clear, speakers often just say:

• 기차역이 가까워요 = The train station is close / nearby

So the sentence does not need to explicitly say to here.

Yes, a sentence like this could also be said with -아서/어서:

• 기차역이 가까워서 택시를 부를 필요가 없겠어요.

That is also natural.

However, -(으)니까 often feels slightly stronger as a reason used for the speaker’s conclusion or judgment. Since the second half contains 없겠어요, which is a judgment/assumption, -(으)니까 fits very well.

So both can work, but -(으)니까 is especially natural here.

They are similar, but not identical.

• 택시를 부를 필요가 없겠어요 = There probably won’t be any need to call a taxi
• 택시를 안 불러도 되겠어요 = It seems we don’t have to call a taxi

These are close in meaning, but:

• 필요가 없다 focuses on lack of necessity
• 안 해도 되다 focuses on it is okay not to do it

Both are common, but 필요가 없다 can sound a little more formal or objective.

없겠어요 is in the polite 해요-style.

Breaking it down:

• 없다 = dictionary form
• 없겠어 = casual
• 없겠어요 = polite

So this sentence is polite and appropriate in everyday conversation.

If you wanted a more formal style, you could say:

• 택시를 부를 필요가 없겠습니다

But 없겠어요 is much more common in ordinary speech.

It sounds a little tentative or reasoned out, not overly blunt.

That comes mainly from -겠어요.

So instead of sounding like a hard fact:

• There is absolutely no need to call a taxi

it sounds more like:

• I don’t think we’ll need to call a taxi
• It seems we won’t need to call a taxi
• We probably won’t need to call a taxi

That kind of soft, inferred statement is very common and natural in Korean.