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activate – v. to cause (a chemical reaction or natural process) to begin
environment – n. all surrounding things, conditions and
influences that affect life
grid - n. a pattern of lines that cross each other to form squares on a piece of paper, a map, etc.
nerve – n. a thin piece of tissue that sends information through the body to and from the brain
position – n. a place; the way of holding the body; the way
a thing is set or placed
positioning – adj. providing information on the location of something
