chaegeul ilgeul ttaeneun angyeongeul sseoyo.

to read

Breakdown of chaegeul ilgeul ttaeneun angyeongeul sseoyo.

• ~을: object particle
• 책: book
• ~는: topic particle

Questions & Answers about chaegeul ilgeul ttaeneun angyeongeul sseoyo.

What does 읽을 때 mean, and why is 읽다 changed to 읽을?

때 means time or when.
So 읽을 때 means when reading or when I read.

The verb 읽다 changes to 읽을 because it is being used before the noun 때. In Korean, verbs often change into a noun-modifying form before words like 때.

So:

• 읽다 = to read
• 읽을 때 = when reading / when I read

Even though -을 often looks like a future-type ending in other contexts, here it is just the normal form used in this pattern.

What does the 는 in 때는 do?

The 는 is a topic marker. It gives 읽을 때 a feeling like:

• as for when I read
• when I read, ...
• in the case of reading, ...

It can also add a slight contrast, as if the speaker means:

• When I read, I wear glasses
  maybe implying but not necessarily at other times.

If you remove it and say 책을 읽을 때 안경을 써요, the sentence is still natural. It just sounds a bit more neutral.

Why are both 책 and 안경 marked with -을?