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: the arrondissement of auxerre is an arrondissement of france.

Output: arrondissement of auxerre


Input: Consider Input: a black powder rocket motor pushes a model rocket using black powder.

Output: black powder rocket motor


Input: Consider Input: the features of a production vehicle or production car are mass-produced identical models, offered for sale to the public.


Output: production vehicle


