Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

platinum is a soft, heavy, white metal.
platinum

eric saade (born 29 october 1990 in helsingborg, sweden) is a swedish singer.
eric saade

the common crane ("grus grus"), also known as the eurasian crane, is a bird of the family gruidae, the cranes.

common crane