hoeui junge silsuro hyudaeponeul tteoreotteuryeosseoyo.

회의 중에 means during the meeting.

• 회의 = meeting
• 중 = middle, while in the middle of
• 에 = a particle that helps mark the time/context

So 회의 중에 is a very common way to say in the middle of a meeting or during a meeting.

Because 중에 specifically emphasizes that something happened while the meeting was going on.

Compare:

• 회의에 = at the meeting / in the meeting
• 회의 중에 = during the meeting / in the middle of the meeting

In this sentence, the speaker wants to say the phone was dropped during the course of the meeting, so 중에 is the natural choice.

실수로 means by mistake or accidentally.

• 실수 = mistake
• -로 here means something like by, through, or as a result of

So 실수로 literally means through a mistake, which naturally becomes by mistake in English.

This is a very common expression:

• 실수로 눌렀어요. = I pressed it by mistake.
• 실수로 지웠어요. = I deleted it by mistake.

Because 휴대폰 is the direct object of the verb 떨어뜨렸어요.

• 휴대폰 = cell phone
• -을 / -를 = object marker

The thing being dropped is the phone, so it takes the object marker:

• 휴대폰을 떨어뜨렸어요. = I dropped the phone.

Since 휴대폰 ends in a consonant, it takes -을.

This is a very important difference.

• 떨어지다 = to fall
• 떨어뜨리다 = to drop something

So:

• 휴대폰이 떨어졌어요. = The phone fell.
• 휴대폰을 떨어뜨렸어요. = I dropped the phone.

In your sentence, the speaker is saying that they caused the phone to fall, even if it was accidental. That is why 떨어뜨리다 is used.

The dictionary form is 떨어뜨리다, which means to drop.

The form breaks down like this:

• 떨어뜨리다 = to drop
• 떨어뜨렸어요 = dropped

It is the polite past tense form. So the speaker is politely saying that the action already happened.

It is polite informal, often called the -어요 style.

• 떨어뜨렸어요 is polite and natural for everyday conversation
• It is appropriate with coworkers, strangers, or anyone you want to speak politely to

Other versions:

• 회의 중에 실수로 휴대폰을 떨어뜨렸어. = casual
• 회의 중에 실수로 휴대폰을 떨어뜨렸습니다. = more formal

So the original sentence sounds polite and natural in many real-life situations.

Yes. Both are commonly used in Korean.

• 휴대폰 = mobile phone / cell phone
• 핸드폰 = cell phone

In everyday conversation, many Koreans say 핸드폰 very often.
휴대폰 can sound a little more neutral or standard.

So these are both natural:

• 회의 중에 실수로 휴대폰을 떨어뜨렸어요.
• 회의 중에 실수로 핸드폰을 떨어뜨렸어요.

Because Korean usually places adverbs like 실수로 before the verb phrase they modify.

So the structure is:

• 회의 중에 = during the meeting
• 실수로 = accidentally
• 휴대폰을 떨어뜨렸어요 = dropped my phone / dropped the phone

This word order is very natural in Korean.
You are basically setting up the context first, then the manner, then the action.

Yes. Korean often leaves out the subject when it is understood from context.

So although there is no explicit 저는 or 제가, the sentence naturally means:

• I dropped my/the phone during the meeting by mistake.

In Korean, if the subject is obvious, it is usually omitted.

If you wanted to include it, you could say:

• 저는 회의 중에 실수로 휴대폰을 떨어뜨렸어요.

But in many situations, leaving 저는 out sounds more natural.

It can mean either, depending on context.

Korean often does not specify possessives like my when they are obvious.

So 휴대폰을 떨어뜨렸어요 could mean:

• I dropped the phone
• I dropped my phone

In real conversation, listeners usually understand it as my phone unless the context suggests a different phone.

Yes, but the nuance is a little different.

• 회의 중에 = during the meeting / in the middle of the meeting
• 회의 동안 = for the duration of the meeting / during the meeting

For a single event happening at some point while the meeting was going on, 회의 중에 sounds especially natural.

So for this sentence, 회의 중에 is usually the better choice:

• 회의 중에 실수로 휴대폰을 떨어뜨렸어요.

회의 동안 is possible, but it can feel a bit less natural for a one-time accidental action.

Yes, it can, depending on tone and context.

Because it includes:

• 회의 중에 = during the meeting
• 실수로 = accidentally

the speaker is giving context and making clear that it was not intentional.

So it can sound like:

• an explanation
• an apology
• a reason for something that happened

For example, if someone asks why the phone screen is cracked, this sentence could be part of the explanation.