经济学
加什河
These unsung passages function as the smaller veins feeding into the main artery of the Grand Canyon, the up-to-18-mile-wide, mile-deep gash in the earth through which 227 miles of the Colorado River snakes.
WSJ: The Grand Canyon's Secret Network
英汉双解词典包含3185865条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。