VOA慢速英语:智利发现美洲最古老人类足迹

fossil – n. part of an animal or plant from thousands of years ago, preserved in rock

excavation – n. the act of digging in the ground to look for objects from the past

barefoot – adj. not wearing shoes or other feet coverings

consistent – adj. always behaving or happening in a similar way

mud – n. a thick liquid mixture of soil and water

artifact – n. a simple object made by people in the past

prehistoric – adj. relating to the time before people could write

glacier – n. very large area of ice that moves slowly down a slope or valley or over a wide area of land