achimeneun chuwoseo koteureul ipgo nagasseoyo.

It was cold in the morning, so I went out wearing a coat.

Breakdown of achimeneun chuwoseo koteureul ipgo nagasseoyo.

• ~를: object particle
• ~는: topic particle
• 춥다: cold
• 입다: to wear

Questions & Answers about achimeneun chuwoseo koteureul ipgo nagasseoyo.

Why is it 아침에는 instead of just 아침에?

아침에 simply means in the morning.

When 는 is added, it becomes 아침에는, which adds a topic or contrast nuance:

• as for the morning
• in the morning, at least
• in the morning though...

So 아침에는 추워서 can sound like:

• It was cold in the morning
• possibly implying but later it wasn’t

Sometimes that contrast is strong, and sometimes it is just a natural topic marker.

What does 추워서 mean grammatically?

추워서 is 춥다 + -어서.

Here, -아서/어서 means:

• because
• so
• sometimes and then, depending on context

In this sentence, it clearly gives a reason:

• 추워서 = because it was cold / since it was cold

So the structure is:

• 아침에는 추워서 = because it was cold in the morning

Why does 춥다 become 추워서?