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I argued with my I.T. teacher who is also our research adviser because as far as my knowledge is concerned I insisted that using they, them and their is acceptable based on APA style. She prohibited us from using she and he, which is understandable, but they, their and them? I don't understand that.
So the words left for us to use is us and students who are the subject of the research and these words eventually become so redundant in our research paper. I think this is very stupid.
Is she correct?