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You need to write conversations and reports with your boss in plain words, super-translated.
Literal
Superior [with-との] conversation [and-や] report [topic-は] super-translated ordinary [gen-の] words [with-で] write [explanation-のです].
A formal business advice sentence. 上司との会話 uses との for the relationship preposition 'with (an attributive)'. 超訳 is a coined neologism: 超 ('super, trans-') + 訳 ('translation'), referring to 'dramatically simplified or paraphrased translation' — originally a publishing buzzword for rendering foreign bestsellers in accessible Japanese. Here extended to 'radically reframed in plain words.' 綴る ('to compose, to string together, to spell') is a literary verb for writing. のです is the explanatory formal copula.