请英语大神帮忙看看我这句错在哪,怎么改?

题目

请英语大神帮忙看看我这句错在哪,怎么改?
Imagining that you sit in your room,all around you were .(主要问题在imagine引出想像情景的用法及在想像情景中是否用虚拟语气),

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