I am writing a mathematical paper. Since my English is not perfect, i am borrowing sentences from English-speaking authors. I have some questions about copy and paste from other papers to my paper. As you know, one needs some definitions and theorems from other papers. I cited all of papers that i used either definition or theorems from them.
1)Can i copy and paste the original either theorems or definition from the papers to my paper or i have to change them?i mean writing somehow that is not as same as original one. Because i have seen English-speaking authors often change original theorem or definition in their papers. On the other hand, i have seen someone does not.
2)As i mentioned, i am borrowing sentences from English-speaking authors. When i look it my introduction, i see this sentence from that paper, that sentence from that paper and ... It makes scene. My supervisor read it and he said it is okay( it is not ambiguous) but i'm scared that referee rejects my paper.