Okay, the user wants me to translate "guru granth sahib" into Simplified Chinese. First, I need to check if the term is already in Simplified Chinese. "Guru Granth Sahib" is the holy scripture of Sikhism, so it's a proper noun. In Chinese, it's commonly translated as "古鲁·格兰特·萨希布" or sometimes "锡克教圣典". However, since the user specified to leave it unchanged if it's already in Simplified Chinese, but "guru granth sahib" is in English. So I should translate it. The standard translation is "古鲁·格兰特·萨希布", which is the direct transliteration. I should make sure there's no existing Simplified Chinese version that's different. I think that's the correct one. Just output the translation without any explanation.