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There is also many people who wrote about this topic.

The topic is not the issue as long as the whole writing is not copy-pasted, you must produce your own content.

They also copy from other sources.

Show me and see the results.

You only mention me.

No, I didn't mention you only. We can't eliminate all the abusers at once. It takes time like you got caught today but it wasn't your first time. Eventually, everyone who plagiarises will see the consequence.

I thought it's okay

Why would you think it's okay? Didn't your big brother tell you about this?