Hxen.com's tips：Every day persisted can learn English well!-->■Learn English Everyday■
glacier – n. a very large area of ice that moves slowly down a slope or valley or over a wide area of land
radioactive – adj. having or producing a powerful and dangerous form of energy (called radiation)
indigenous – adj. native; from a place
harmony – n. a pleasing combination or arrangement of different things
make a fool of – expression to deceive or trick someone so that they appear to be foolish
credibility – n. the quality of being believed or accepted as true, real, or honest
