VOA慢速英语:The Grand Canyon: A Sight Beyond Words

enormous - adj. very great in size or amount

speechless - adj. unable to speak because of anger, surprise, etc

minerals - n. a substance (such as quartz, coal, petroleum, salt, etc.) that is naturally formed under the ground

helicopter - n. an aircraft that can stay in the air without moving forward and that has metal blades that turn around on its top

access - v. to be able to use, enter, or get near (something)