jumareneun chaegeul manhi ilgeoyo.

On weekends, I read a lot of books.

Breakdown of jumareneun chaegeul manhi ilgeoyo.

• 읽다: to read
• ~을: object particle
• 책: book
• ~는: topic particle

Questions & Answers about jumareneun chaegeul manhi ilgeoyo.

Why is it 주말에는 instead of just 주말에?

주말에는 is 주말에 + 는.

• 주말에 means on the weekend / at the weekend
• adding 는 makes it a topic and often adds a slight sense of contrast

So 주말에는 책을 많이 읽어요 can feel like:

• As for weekends, I read a lot of books
• On weekends, I read a lot

It may suggest something like on weekends (as opposed to weekdays), I read a lot, even if that contrast is only implied.

What exactly does 는 do here?

In this sentence, 는 is the topic particle.

It tells the listener what time frame the speaker is talking about: when it comes to weekends.

Because it comes after 에, the full form is 에는. This is very common in Korean:

• 학교에 → 학교에는
• 집에 → 집에는
• 주말에 → 주말에는

It does not change the basic meaning of 에; it adds a topic/contrast nuance.

Why does 책 have 을 after it?