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: goldenrods are any of the about 150 species of weedy herbs that make up the genus solidago.

Output: goldenrod


Input: Consider Input: caledonian stadium is a scottish football stadium.

Output: caledonian stadium


Input: Consider Input: the great western main line is a main line railway in england, that runs westwards from london paddington to bristol temple meads.


Output: great western main line