该, as a pronoun, means "this, that, the above-mentioned, the said, etc.". e.g., 该案 this/that/... case; 该层楼 this/that/... floor; 该杯 this/that/... cup of juice 该校 the this/that/above-mentioned/... school; 这是本地最大的医院，该医院有七百张病床。 This is the biggest hospital in the locality. It has 700 beds. There exists quite a lot of examples. The use of “该” is roughly equivalent to the English word "this" or "that". This usage is mainly heard in written language, official words or other formal occasions (in newspaper, articles, tv programs, speeches, classes, etc.). It is not often heard in spoken language. We don't use it in everyday speak a lot. By the way, it is used a lot in some dialect in some area of China, e.g. “该搭” means "here" in 吴语（Wu Chinese）. It doesn't matter, just fun.

Just as Yule said. 该本，该人，该动物？ all of three are wrong,we dont use it like this. "该" seems only to be used before “place” 、 “area”、 "institution" or "organization", and you can only find them from newspapers、TV news. for expamle 该地区，该校，该法院，该组织，该机构 as for "该本，该人，该动物？" ,I think the right way is : "这本，这个人，这只动物".

該本 is unfinished. You can say 該本小說, 該本書,etc. It's hard to think of examples as we don;t really use it this case a lot. You would hear it in report or read it in a article but it's still rare. In daily life , we use "該" in most cases as should. Like 我"該"去學習了 which means I should study.