naembi ttukkeongeul dadeumyeon muri deo ppalli kkeulheoyo.

-으면 is a conditional ending meaning if or when.

So 닫으면 means if you close it or when you close it.

In this sentence, it has a general-fact feeling:

• 냄비 뚜껑을 닫으면 = If/when you close the pot lid
• 물이 더 빨리 끓어요 = the water boils faster

Korean often uses -으면 / -면 for things that are generally true, not just one specific future event.

Because the verb stem 닫- ends in a consonant.

The rule is:

• after a vowel: -면
• after a consonant: -으면

Examples:

• 가다 → 가면
• 먹다 → 먹으면
• 닫다 → 닫으면

So 닫으면 is the correct form.

뚜껑 means lid, and -을 is the object marker.

So:

• 뚜껑을 닫다 = to close the lid

The lid is the thing being closed, so it takes the object marker 을.

Because 뚜껑 ends in a consonant, it takes -을 rather than -를.

냄비 means pot, and 뚜껑 means lid.

Put together, 냄비 뚜껑 means pot lid or the lid of the pot.

Korean often puts nouns together like this, similar to English compound nouns:

• 커피 잔 = coffee cup
• 책 표지 = book cover
• 냄비 뚜껑 = pot lid

So this is a very natural noun combination.

Because 물 is the subject of 끓어요.

The verb 끓다 means to boil in the sense that something boils on its own. That makes water the thing doing the action grammatically, so it takes the subject marker 이/가.

• 물이 끓어요 = The water boils / is boiling

If you used 물을, it would sound like water is the object of some other action.

This is an important Korean distinction:

• 끓다 = to boil
• 끓이다 = to boil something

So:

• 물이 끓어요 = The water boils.
• 물을 끓여요 = I boil the water.

This is a very common question.

• 끓다 = to boil
  The thing itself boils.
• 끓이다 = to boil something
  Someone causes it to boil.

Examples:

• 물이 끓어요. = The water boils / is boiling.
• 물을 끓여요. = I boil the water.

In your sentence, 물이 더 빨리 끓어요 uses 끓다 because the water is the thing that boils.

더 means more, and 빨리 means quickly / fast.

Together:

• 더 빨리 = more quickly or faster

So:

• 물이 더 빨리 끓어요 = the water boils faster

A useful point:

• 빠르다 = to be fast
• 빨리 = fast/quickly, used as an adverb

Yes, 빠르게 is grammatically possible, but 빨리 is more common and more natural in everyday speech.

Compare:

• 더 빨리 끓어요 = very natural
• 더 빠르게 끓어요 = possible, but a bit less everyday/plain

So learners should recognize both, but 빨리 is the one you will hear more often in this kind of sentence.

끓어요 is the polite present-tense form of 끓다.

It is in the standard polite style often used in conversation, explanations, and textbooks.

Levels you might compare:

• 끓어 = casual
• 끓어요 = polite
• 끓습니다 = formal

So 끓어요 is a natural everyday polite ending.

It usually sounds like a general fact or general advice:

• If you close the pot lid, the water boils faster.

Korean often uses the present tense for general truths, habits, and scientific-type statements.

So even though English might sometimes say will boil faster, Korean naturally says 끓어요.

Korean often leaves out subjects when they are obvious or not important.

In 냄비 뚜껑을 닫으면, the understood subject is something like:

• you
• someone
• one

So the meaning is basically:

• If you close the pot lid...
• If someone closes the pot lid...

Korean does this very often, and it sounds completely natural.

Yes, to some extent.

The basic structure here is:

• condition + result
• 냄비 뚜껑을 닫으면 / 물이 더 빨리 끓어요

This is the most natural order for this sentence.

You can sometimes move things around for emphasis, but Korean usually keeps the verb at the end of each clause. So these parts should stay intact:

• 뚜껑을 닫으면
• 물이 더 빨리 끓어요

For learners, the original word order is the best one to use.

It is pronounced more like 다드면.

That happens because the final consonant in 닫 connects to the following vowel in -으면.

So:

• spelling: 닫으면
• pronunciation: 다드면

This kind of sound change is very common in Korean pronunciation.

It is pronounced roughly like 끄러요.

So:

• spelling: 끓어요
• pronunciation: 끄러요

This is one of those words where the spelling and the actual spoken form are not obvious to beginners, so it is very normal to find it confusing.