I encountered the sentence:
I understand that: 送って translates to a verb meaning "to send", or I assume in this case "sending" due to the "te-form" being used.
I also understand that: くれた translates to a verb meaning "to give (to be given)"
So a literal translation of 両親が私にはがきを送ってくれた would mean:
My parents, to me, a postcard, Sending and given.
My parents sent and gave me a postcard.
So I don't quite understand why you must say "they sent and gave me a postcard" instead of just "they sent me a postcard". For example
Is there a grammatical/logical explanation for this? Or is this simply just how it's done for no reason?