1) The red stuff inside a thermometer.
2) The first planet from the sun
3) A car company
4) Acting like, portraying, or a person who is being like the late Queen lead singer Freddie Mercury.
1) Young Steve broke open the thermometer and tasted the red stuff inside, called mercury.
2) No humans can ever inhabit the planet Mercury, because one side of the planet is too hot, while the other side is too cold.
3) Mr. Poe recently bought a 1999 Mercury Villiager, because his 1988 Honda Accord exploded.
4) "John is being such a mercury today," remarked Joanne, "He is wearing a spandex jumpsuit for no reason and he keeps ending everything he says with "Darling" or "Dear"."