I would have gone to visit him in the hospital had it been a

翻译：我本来想到医院看你,但是整个上周我都在茫茫碌碌,如果真正可能的话（可以去看你）.
这是虚拟语气的句子,表示对过去的虚拟,说明这件事情已经过去,表示遗憾呢
had it been at all possible 省略 if it had been possible at all.
at all 是加强语气的短语
but I was fully occupied the whole of last week.be occupied表示忙碌的状态,
occupied是形容词,忙碌的相当于busy；last week 这是过去的时间,所以用过去时
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