第一句翻译得很好。 第二句可以翻译成，我很喜欢住在这儿，因为这里有很多中国留学生。这样翻译比较有逻辑关系。 第三句，他很忙，晚上经常（or 经常）在办公室加班。翻译成“加班”比较合适。可以用“常常”，也可以用“经常”，是一样的意思。 sorry,the first sentence you translated well. and the second, you had better translated into "我很喜欢住在这儿，因为这里有很多中国留学生",because the reason you like living here is many Chinese students here, so you had better add "因为(because)", and it sounds more logical and easy to understand by Chinese. 3.办事情->加班, work extra hours we Chinese say 加班, 办事情 means do something but we don't know the specifit, but you say 加班 we can understand things about your work. I wish it will help you:)

I have not finished reading the book bought last month 我还没有看完上个月买的书 估计是笔误吧

都很好！ 如果“我很喜欢住在这儿，（因为这儿）中国留学生很多。”就更完美了