Learn Hardcore Korean: chinguwa hamkke gongwoneseo undonghaeyo.

The particle -와 attaches to a noun ending in a vowel (here, 친구) to mean “and” or “with.” In 친구와 함께, it marks 친구 as the person you’re together with.
• If a noun ends in a consonant, use -과 (e.g., 선생님과 함께).
• In casual speech, you can also say 친구랑 instead of 친구와.

What does 함께 mean, and how is it different from 같이?

함께 is a Sino-Korean adverb meaning together. 같이 is the native Korean equivalent, also meaning together.
• 함께 often sounds more formal or literary.
• 같이 is more colloquial and common in everyday conversation.

Why is 공원에서 used instead of 공원에?

The particle -에서 marks the location where an action takes place (“at/in the park”).
• 공원에서 운동해요 = “I exercise at the park.”
The particle -에 (without 서) marks a static location or a direction (“to/at the park”).
• 공원에 가요 = “I go to the park.”

Why don’t we use an object marker after 운동? Shouldn’t it be 운동을 해요?

운동하다 is a verb formed by combining the noun 운동 (“exercise”) with 하다 (“to do”). When you conjugate 하다, the noun + 하다 becomes one verb, so you typically drop the object marker:
• 운동해요 (natural).
You can say 운동을 해요 for extra emphasis or clarity, but in most cases learners use the contracted 운동해요.

How is 운동해요 formed from 운동하다?

Start with 운동하다 (dictionary form).
Remove 다: stem is 하.
Add 어요 for present-tense politeness: 하 + 어요 = 하여요.
Contract 하여요 → 해요.
Combine with 운동 → 운동해요.

Can I change the level of formality by altering -해요?

Yes. The ending -해요 is present-tense polite (요-form). Other options:
• Formal written/spoken: -합니다 → 공원에서 운동합니다.
• Informal/casual (close friends): drop -요 → 공원에서 운동해.

Is the word order fixed in 친구와 함께 공원에서 운동해요?

Korean is flexible as long as the verb stays at the end. You can reorder phrases for emphasis:
• 공원에서 친구와 함께 운동해요 (emphasize location)
• 친구와 공원에서 함께 운동해요 (emphasize the “together” aspect)
Meaning remains the same.