Indeed plagiarism is a crime in writing, and I second your statement that in the beginning many people join steemit but they lost the energy because of plagiarism, they get warnings and then they stop posting. So this is why these achievements are important so that we can learn all methods of sourcing and cite.

Please add this remark at the end of your achievement as mentioned by cryptokannon.

please put a remark,
"I have read and understood the Steemit Etiquette on Steemit Community and will do my best to embrace them" at the end of this task post.

You can enclose the source link into shorter form too by following syntax;

[source/reference] (link of source) --> I have given a gap between the square bracket and round bracket but for applying it there should be no gap in between any of the two brackets.
It will appear like this source

Similarly, if you want to quote someone's message use this symbol ">"

message/saying

Happy steeming :)