oneul bibimbabi jogeum maewoseo mureul manhi masyeosseoyo.

오늘 is a time word, and time expressions in Korean very often appear without a particle. So 오늘 simply means today here.

You could also say 오늘은, but that would add a topic/contrast feeling, like as for today or today, at least. In this sentence, plain 오늘 sounds natural and neutral.

비빔밥이 uses the subject marker 이/가, because the sentence is describing the bibimbap as having the property spicy:

• 비빔밥이 매워서 = because the bibimbap was spicy

If you said 비빔밥은, that would make bibimbap the topic, often with a slight contrast or emphasis:

• 비빔밥은 조금 매워서... = As for the bibimbap, it was a little spicy, so...

Both are possible, but 이/가 is very natural when introducing the cause as a specific fact.

조금 means a little or slightly.

So:

• 조금 매워서 = because it was a little spicy

It softens the adjective 맵다 (to be spicy). English speakers often think of 조금 as modifying nouns, but it also commonly modifies adjectives and verbs.

This is because 맵다 is a ㅂ-irregular adjective.

When a ㅂ-irregular word is followed by a vowel-starting ending like -아/어서, the ㅂ changes to 우, and then combines naturally:

• 맵다 → 매워요
• 맵다 → 매워서

So 매워서 is the correct form, not 맵어서.

Other common examples:

• 덥다 → 더워요
• 어렵다 → 어려워요

Here, -아서/어서 means because or so, connecting the reason to the result.

So this part means:

• 조금 매워서 물을 많이 마셨어요
• Because it was a little spicy, I drank a lot of water

In many sentences, -아서/어서 can sound more natural than directly translating English because.

Both can express a cause/result relationship, but they work differently.

• 매워서 connects the reason directly to the verb/adjective:
  It was spicy, so...
• 그래서 is a separate connector meaning so / therefore.

Compare:

• 비빔밥이 조금 매워서 물을 많이 마셨어요.
  = Because the bibimbap was a little spicy, I drank a lot of water.

• 비빔밥이 조금 매웠어요. 그래서 물을 많이 마셨어요.
  = The bibimbap was a little spicy. So I drank a lot of water.

Both are fine, but the original sentence is more smoothly connected.

물 is the object of the verb 마셨어요 (drank), so it takes the object marker 을/를.

• 물
  • 을 = 물을

This shows that water is the thing being drunk.

많이 is an adverb, so it modifies the verb 마셨어요:

• 물을 많이 마셨어요 = drank a lot of water / drank water a lot

This is very natural in Korean.

You could also say:

• 많은 물을 마셨어요 = drank a lot of water

But that structure uses 많은 to modify the noun 물. In everyday speech, 물을 많이 마셨어요 is extremely common and natural.

마셨어요 is:

• past tense
• polite speech style

It comes from 마시다 (to drink):

• 마시다 → 마셨어요

So the sentence sounds polite and appropriate for normal conversation.

Yes, Korean word order is more flexible than English, as long as the particles and meaning stay clear.

For example, these are possible:

• 오늘 비빔밥이 조금 매워서 물을 많이 마셨어요.
• 비빔밥이 오늘 조금 매워서 물을 많이 마셨어요.
• 오늘 물을 많이 마셨어요. 비빔밥이 조금 매워서요.

But the original order is very natural because it presents:

1. the time,
2. the reason,
3. the result.

Yes. Korean often omits subjects when they are understood from context.

So even though 저는 or 제가 is not stated, the sentence naturally implies:

• (I) drank a lot of water

This is extremely common in Korean. You do not need to include I unless you want emphasis or contrast.

Yes, but the meaning would change.

• 조금 매워서 = because it was a little spicy
• 너무 매워서 = because it was too/very spicy

So:

• 오늘 비빔밥이 너무 매워서 물을 많이 마셨어요.
  = Today the bibimbap was so spicy that I drank a lot of water.

Both are natural; they just express different degrees of spiciness.