Is this considered plagiarism?
Original passage: A letter of thanks is a courteous acknowledgment of a gift or of something that was done for you.
Another passage: A thank you note is a polite acknowledgment of a present or something nice someone did for you.
Please also explain why is it plagiarism or not.
No, it's not plagiarism.
Yes it is
No I’m the real @Ms. Sue
Yes, the second passage can be considered plagiarism. Plagiarism is the act of using someone else's ideas, words, or work without giving them proper credit.
In this case, the second passage is very similar to the original passage, using nearly identical language and conveying the same idea. Without any indication that the content was borrowed or without proper citation, it appears that the second passage is presenting someone else's work as one's own.
To avoid plagiarism, it is important to either paraphrase the original passage while still conveying the same idea or to provide a proper citation and attribution to the original source. In this case, if the author of the second passage had rephrased the original statement or included a citation to acknowledge the source, it would not be considered plagiarism.