weeds – n. a plant that grows very quickly where it is not wanted and covers or kills more desirable plants
cemetery – n. a place where dead people are buried
grave – n. a hole in the ground for burying a dead body
poison – n. a harmful or deadly substance
herbicide – n. a chemical used to destroy plants or stop plant growth
sustainable – adj. able to last or continue for a long time; involving methods that do not completely use up or destroy natural resources
pesticide – n. a chemical that is used to kill animals or insects that damage plants or crops