TASK DEFINITION: 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.
PROBLEM: in egyptain mythology sopdet was the goddess of the star sothis.

SOLUTION: sopdet

PROBLEM: a nature reserve (preserve or (national/nature) conserve) is a protected area.

SOLUTION: nature reserve

PROBLEM: professor hugo strange is a fictional evil scientist character who appears in the batman comic books by dc comics.

SOLUTION:
hugo strange