I's so ashamed that I did not realize I answered your question in a wrong place untill just now.I will complicate this answer continuely.400 mm precipitation line as dividing line plays an important role in climate，vegetative cover，as well as livestock breeding.As for fish,marine fishery locates in coastal areas.The top four famous fishing groud in China:Bohai fishing ground,South China Sea fishing ground,Zhoushan fishing ground,Beibu Gulf fishing ground(You can have acess to specific information in Wikipedia ).Freshwater fish mainly lacates in rivers and lakes in China,especially in eastern China and southen China,due to flat terrain and abundant water resources.Thus,a number of southerners have their own fish pond. Hmm~That's all.I hope you will be pleased with my answer.

First of all,I must admit there is something wrong in my words,so please try to understand.You can ask me when you have question.China has vast territor，different areas rase different regions. 1、Animal Husbandry:mainly located in the northern arid and semi - arid area and Tibetan Plateau.Chinese four major pastoral areas:Inner Mongolia(famous for Three hippos, Sanhe cattle), Xinjiang(fine-wool sheep), Qinghai, Tibet(Tibetan sheep and yak). All the above is main distribution area.Now some dairy companies have there own pasture not only in main distribution area,but also have smaller ones in some city without geographical restrictions. 2、Farming area animal husbandry:Refering to the pig, cattle, sheep and chickens, ducks, geese and other poultry,which plays a important role in China.These area are not suitable for the development of planting industry and far away from city.As for self-employed persons,theycan have theie own hoggery,hennery and ect，which is under the few limits of natural,because they are indoor industrializ. That's all for today.There is something about fish that I will complicate tomorrow.

在莫斯科之前，哪个城市曾经作为俄罗斯的首都？

"I'm reading this book"means"我在看这本书"。“我看书这书”is ungrammatical in Chinese.I think it should be “我在看书”or"我在看这本书"。”在”is a preposition.And in Chinese,"+ing" which means present tense，it can be better if containing"正在" when transfering,a bit like"now" in Engilsh.