Congested railways and ports have also been a problem, especially for coal and iron ore.
拥挤的铁路和港口也已经造成了问题，尤其是对煤矿业而言。
2
The area being talked about is very heavily congested with pigeons because the raptor problem became so great elsewhere that RACES have moved to east England.
出事区域有大量赛鸽，因为在其他地区肉食鸟的问题非常严重，所以比赛搬到了英格兰东部举行。
3
The congested traffic has become a serious problem for many cities with their steadily increasing population, and the construction of subways is viewed as an effective solution to the problem.