mesijireul bonaegi jeone beonhoreul dasi hwaginhaeyo.

-기 전에 means before doing ....

It is made from:

• verb stem + -기 → turns the verb into the act of doing
• 전에 → before

So:

• 보내다 = to send
• 보내기 = sending / the act of sending
• 보내기 전에 = before sending

So 메시지를 보내기 전에 means before sending the message.

-를 is the object marker. It shows what is being acted on by the verb.

Here, the verb in the first part is 보내다 = to send, and the thing being sent is 메시지 = message.

So:

• 메시지 = message
• 메시지를 = the message (as the object)

In other words, 메시지를 보내다 means to send a message.

Yes. This sentence has two different verbs in two different parts, so each verb can have its own object.

1. 메시지를 보내기 전에

   • verb: 보내다
   • object: 메시지를

2. 번호를 다시 확인해요

   • verb: 확인하다
   • object: 번호를

So the sentence is not giving one verb two objects. It has:

• send the message
• check the number again

That is why you see -를 twice.

Literally, 번호 means number. In this sentence, it usually means something like:

• a phone number
• the recipient’s number
• some contact number you should verify before sending

So it is often understood as the number you are about to send the message to.

Korean often leaves this kind of detail to context.

다시 means again.

Here it means check again or double-check.

So:

• 확인해요 = check / confirm
• 다시 확인해요 = check again / confirm again

In natural English, this often sounds like double-check the number.

The dictionary form is 확인하다 = to check / to confirm.

To make it polite in the -아/어요 style:

• 확인하다
• 확인하여요 (older/full form)
• 확인해요 (contracted, normal modern form)

So 하다 verbs usually become 해요, not 하요.

Examples:

• 공부하다 → 공부해요
• 이해하다 → 이해해요
• 확인하다 → 확인해요

확인해요 is in the polite informal style, often called the -해요 / -아요 / -어요 style.

It is:

• polite
• common in everyday conversation
• softer than a direct command
• less formal than 확인합니다

Compare:

• 확인해요 = polite everyday style
• 확인합니다 = more formal
• 확인하세요 = please check

So this sentence sounds like a polite statement, reminder, or gentle instruction.

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

So this sentence could mean different things depending on the situation:

• I check the number again before sending the message.
• You should check the number again before sending the message.
• We check the number again before sending the message.
• Before sending a message, check the number again.

Korean does this very often. The listener usually understands the subject from the situation.

Yes, 확인해요 is a present-style form, but in Korean that form can also express:

• habits
• general truths
• routines
• instructions stated gently

So this sentence can mean something like:

• I check the number again before sending a message.
• We check the number again before sending a message.
• Check the number again before sending the message.

If you want a clearer command, you could say:

• 메시지를 보내기 전에 번호를 다시 확인하세요. = Please check the number again before sending the message.

So 확인해요 here is softer and more neutral.

In many contexts, 전 and 전에 are both seen, but with this grammar pattern, -기 전에 is the standard form learners should use.

So:

• 보내기 전에 = natural and standard
• 보내기 전 = possible in some shortened or noun-like expressions, but less basic for beginners

If you are learning the pattern, it is safest to remember:

• verb stem + -기 전에 = before doing

Yes. 확인 is usually pronounced more like 화긴 in natural speech.

So:

• spelling: 확인해요
• natural pronunciation: 화긴해요

That happens because Korean pronunciation often changes slightly for easier flow, even when the spelling stays the same.

So if you hear something like 화긴해요, that is still 확인해요.

Yes, that is a very natural translation.

Even though 다시 확인하다 literally means check again, in English the best natural translation is often:

• double-check the number before sending the message

That captures the real meaning very well.