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mission – n. a task or job that someone is given to do
clue – n. something that helps a person find something, understand something, or solve a mystery or puzzle
beach – n. an area covered with sand or small rocks that is next to an ocean or lake
alien – n. from somewhere other than the planet Earth
familiar – adj. frequently seen, heard, or experienced
propeller – n. a device with two or more blades that turn quickly and cause a ship or aircraft to move
crust – n. a hard layer on the surface of something
