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.

Input: Consider Input: sonic firestorm is the second studio album by english power metal band dragonforce released through on may 11, 2004.

Output: sonic firestorm


Input: Consider Input: serie d is the top level of the non-professional football clubs in italy.

Output: serie d


Input: Consider Input: prunus salicina, commonly called the japanese plum or chinese plum, is a small deciduous tree native to china.


Output: japanese plum