Learn Hardcore Korean: chinguhante pati sajineul da bonaesseoyo. - I sent all the party photos to my friend.

-한테 is a colloquial dative particle that marks the recipient or target of an action (“to someone”). Here, it tells us that the photos were sent to a friend.

Can I replace 친구한테 with 친구에게?

Yes. 친구에게 is the more formal equivalent of 친구한테. Both mark the indirect object, but -에게 sounds slightly more polite or written, whereas -한테 is common in everyday conversation.

Why is there no plural marker on 사진 (“photos”)?

Korean often omits the plural marker -들 when the quantity or context is clear. Here, the word 다 (“all”) already tells us you sent all the photos, so adding 들 to make 사진들 is unnecessary (though not strictly wrong).

What does 다 mean here, and why is it placed before 보냈어요?

In this sentence 다 functions as an adverb meaning “all” or “completely.” It modifies 보냈어요 to show that you sent all of the party photos. Placement before the verb is normal for adverbs in Korean.

Why is 을 attached to 사진?

-을 is the object marker for nouns ending in a consonant. It tells us that 파티 사진 is the direct object of 보냈어요 (“sent”). Without it, the sentence would be ambiguous.

The subject “I” isn’t in the sentence. Is that okay?

Yes. Korean frequently omits the subject when it’s understood from context. Here, “I” is clear from the verb ending -어요 (first person) and the conversation context.

What tense and politeness level is 보냈어요?

보냈어요 is the past tense (sent) polite form. It comes from the verb 보내다 (to send) + past suffix -었- + polite ending -어요.

Could I change the word order, for example, put 다 right after 친구한테?

You could say 친구한테 다 파티 사진을 보냈어요, but that slight reordering shifts emphasis onto “all” (as in “I even sent all of them to my friend”). The original order (파티 사진을 다 보냈어요) naturally focuses on what was sent (the photos) and then clarifies quantity.