Am I violating MIT?

Question

Copyright

1. Am I violating MIT if I remove that person's copyright from the library I use?
2. And if I change it, do I still need to leave the copyright of the original author?
3. How to leave his copyright?

Answer 1

The wiki has a translation of the license, which clearly states that 1 - violate, 2 - should be left.
3. At the very top of the license, the year and the owners of the rights are indicated (an example is in the same wiki). There must be the original developer whose solutions you used, and yourself.
PS: If you are changing significantly, then you can stop worrying and indicate only yourself.