oneul sueop naeyongi eoryeowoyo.

The content of today’s class is difficult.

Breakdown of oneul sueop naeyongi eoryeowoyo.

• ~이: subject particle
• 오늘: today
• 수업: class
• 어렵다: difficult
• 내용: content

Questions & Answers about oneul sueop naeyongi eoryeowoyo.

What does the particle 이 after 내용 do, and why not 은/는?

• 이 marks the grammatical subject: the thing that is “difficult” is the content.
• 은/는 would make it a topic: 수업 내용은 어려워요 = “As for the class content, it’s difficult” (contrastive or topic-setting).
• Also, use 이 after a noun ending in a consonant sound and 가 after a vowel. 내용 ends with the consonant [ŋ], so it takes 이.

Why is there no 의 between 수업 and 내용? Is 수업의 내용 wrong?

• Korean often forms noun–noun compounds without 의 when the relationship is clear: 수업 내용 is a common compound.
• 수업의 내용 is correct but sounds more formal/emphatic or written.
• In everyday speech, 수업 내용 is preferred.

Does 오늘 modify 수업 only, or the whole sentence?

• Here 오늘 수업 means “today’s class,” so 오늘 modifies 수업.
• If you want to highlight the day as a topic/contrast, use 오늘은 수업 내용이 어려워요 (“As for today, the class content is difficult”).

Can I just say 수업이 어려워요? What’s the nuance difference?

• 수업이 어려워요: the class overall is difficult (pace, delivery, everything).
• 수업 내용이 어려워요: the subject matter itself is difficult.
• Choose based on what you want to emphasize.

What politeness level and form is 어려워요?

• Polite informal (요-form) present: natural in most conversations.
• Dictionary form: 어렵다.
• More formal: 어렵습니다. Casual: 어려워. Plain/descriptive base (e.g., in dictionaries): 어렵다.

Why does 어렵다 become 어려워요? What rule is this?

• It’s a ㅂ-irregular descriptive verb. Before a vowel (like -어요), ㅂ → 우, which contracts with 어 to 워: 어렵 + 어요 → 어려워요.
• Similar: 덥다 → 더워요, 춥다 → 추워요. Note the variant with some verbs: 돕다 → 도와요.

Is this present tense? How do I say it in the past or future?

• Present/state: 어려워요.
• Past: 어려웠어요 (e.g., 오늘 수업 내용이 어려웠어요).
• Future/expectation: 어려울 거예요 (e.g., … 어려울 거예요).

Why is the subject marker on 내용 and not on 수업?

• 내용 is the head noun (“content”); 수업 modifies it. The subject marker attaches to the head: 수업 내용이 ….
• If you insert 의 (수업의 내용), it’s even clearer that 내용 is the head.

Can I drop particles in this sentence?

• In casual speech, yes: 오늘 수업 내용 어려워요 is common and natural.
• In careful speech/writing, keep 이 to avoid ambiguity: 오늘 수업 내용이 어려워요.

How do I pronounce the whole phrase naturally?

• Across the boundary, 수업 내용이 often sounds like “수엄 네용이” due to nasalization (ㅂ + ㄴ → ㅁㄴ).
• 어려워요 has the “워” [wɔ] sound (어 + 우 → 워). Don’t add an extra syllable.

Do I need a plural marker for “contents”? Should it be 내용들?

• No. 내용 already covers “content/contents.” Use 내용들 only when you explicitly mean separate, countable items and want to stress plurality.

What’s the difference between 어렵다 and 힘들다 here?

• 어렵다: conceptually/intellectually difficult (hard to understand).
• 힘들다: burdensome/tough (physically or mentally taxing).
• 수업 내용이 힘들어요 shifts the nuance to the workload/process being tough.

How can I soften or adjust the degree of difficulty?

• Softer: 좀/조금 어려워요 (“a bit hard”).
• Stronger: 아주/매우/정말 어려워요. In casual speech, 너무 어려워요 often means “very hard” (not only “too hard”).

Is 오늘의 수업 내용 okay?

• Yes. 오늘의 수업 내용 is grammatical and sounds formal/written. In conversation, 오늘 수업 내용 is more natural.

Should it be written 수업내용 or 수업 내용?

• Standard spacing is 수업 내용 (with a space). You may see 수업내용 informally, but the recommended form uses a space.

How would I tell the teacher politely that it was difficult today?

• Use a softener and past tense: 오늘 수업 내용이 좀 어려웠어요.
• More formal: 오늘 수업 내용이 조금 어려웠습니다.

How can I be more specific that it’s the content we covered today?

• Say 오늘 수업에서 배운 내용이 어려워요 (“The content we learned in class today is difficult”).