modu gati ibeon haengsareul jal mamurihaeyo.

They are related, but not identical.

• 모두 = everyone / all
• 같이 = together

So 모두 같이 means something like everyone together or all together.

Using both adds a feeling of group unity and encouragement. It can sound slightly emphatic, like the speaker is saying:

• Let’s all work together
• Everyone, together, let’s finish this well

It is natural, especially in team or event contexts.

이번 means this time or this when talking about the current occasion.

In this sentence:

• 이번 행사 = this event

A useful comparison:

• 이 행사 = this event
• 이번 행사 = this event / this time’s event

이번 often emphasizes that this is the current or present occasion.

The 를 is the object particle.

• 행사 = event
• 행사를 = the event, marked as the object of the verb

The verb 마무리하다 means to wrap up / bring to a close / finish up, and the thing being wrapped up is the event, so it takes the object particle:

• 이번 행사를 마무리해요 = let’s wrap up this event

It is 를 rather than 을 because 행사 ends in a vowel.

Yes, 잘 literally means well, but in this kind of sentence it often means:

• successfully
• smoothly
• properly
• without problems

So here 잘 마무리해요 does not just mean finish skillfully. It has the sense of:

• let’s wrap this up successfully
• let’s bring this to a good close

This is a very common use of 잘 in Korean.

마무리하다 means to finish up, wrap up, bring something to a close, or complete the final part of something.

It is often used for things like:

• events
• projects
• meetings
• tasks
• speeches

So 이번 행사를 잘 마무리해요 is not just end the event in a mechanical sense. It suggests bringing the event to a satisfying or successful conclusion.

Both are possible, but they feel a little different.

• 마무리해요 = polite, softer, more conversational
• 마무리합시다 = polite, but more formal and more directly like let’s do it

In context, 마무리해요 often sounds like a gentle suggestion, encouragement, or team-oriented proposal.

So this sentence feels natural if a speaker is encouraging a group in a friendly or professional setting.

Very roughly:

• 마무리해요 = let’s wrap it up / let’s bring it to a good close
• 마무리합시다 = let us wrap it up

Yes. Korean often leaves the subject unstated when it is obvious from context.

Here, the implied subject is something like:

• 우리
• 우리 모두
• we all

Even though 우리 does not appear, the meaning is understood from 모두 같이 and the overall tone of the sentence.

So the sentence naturally feels like the speaker is addressing a group and including themselves in the action.

They are very similar, and in this sentence you often could replace it.

• 같이 = together
• 함께 = together, often a bit more formal or written-sounding

So this would also work:

• 모두 함께 이번 행사를 잘 마무리해요.

The difference is mostly nuance:

• 같이 sounds a bit more conversational
• 함께 can sound slightly more polished or formal

Both are natural.

Korean word order is fairly flexible, especially with adverbs and topic-like elements, as long as the relationships are clear.

The given sentence:

• 모두 같이 이번 행사를 잘 마무리해요.

could also appear in slightly different orders, such as:

• 이번 행사를 모두 같이 잘 마무리해요.
• 이번 행사를 잘 마무리해요, 모두 같이.

But the original order sounds natural because it begins with the team feeling:

• everyone together → this event → successfully wrap up

That gives it a motivating, speech-like tone.

It is best understood as a polite inclusive suggestion or encouragement.

It is not a harsh command. It sounds more like:

• Let’s all wrap up this event well
• Let’s work together to bring this event to a successful close

So the tone is cooperative and motivating, especially in workplace, school, volunteer, or event settings.