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You have to read what the Prophet salla Allahu alaihi wa sallam had taught us to say in prayer in Arabic. You can’t translate that. As for Du’ah, the Prophet salla Allahu alaihi wa sallam had told us that making Du’ah in Sujood is acceptable but he didn’t tell us to make it in a specific language. Therefore, it is permissible to only make Du’ah in your language.