请将下面这段话翻译成英文：
打车难已经成为大城市人们生活中较为普遍的问题。城市人口规模的扩大，人类社会活动的不断多元(diversification)化都增加了对出租车的需求。随着城市交通拥堵状况不断加剧，为避免堵车影响收人，上下班高峰时段很多司机不愿意跑拥堵路段和主城区，导致市民在一些交通枢纽、商业中心、医院附近很难打到出租车。城市建设影响了出租车的使用效率。出租车行业不规范，拒载行为屡屡发生，这也是导致打车难的人为因素。
参考译文：
It has been a common problem in large city residents' life that it's hard to take a taxi. The increase of urban population and diversification of social activities make the demand for taxi rise. As the traffic jam becomes worse in cities，to guarantee personal income, many taxi drivers refuse to drive on busy roads and main urban areas, which makes it difficult for many citizens to take a taxi near some transportation junctions, commercial centers and hospitals. City construction affects the efficiency of taxi. Being not standard in the taxi industry and taxi drivers' often refusing to take passengers are the human factors that make it difficult to take a taxi.
词句点拨
1.打车难:可译为it's hard to take a taxi,作为problem的同位语，意义表达清楚自然。
2.增加了对出租车的需求:可译为make the demand for taxi rise。
3.为避免堵车影响收入:可灵活地译为to guarantee personal income。采用逆向译法，上下文反复出现“堵车”这个词，所以可以省略。
4.出租车行业不规范，拒载行为屡屡发生:这里是说明原因，为了句式简明，可以处理为动名词和独立主格的形式，直接充当句子主语。
5.人为因素:可译为human factor。