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.

Example Input: james webb space telescope (jwst) is a telescope that will be put into space.
Example Output: james webb space telescope

Example Input: ricardo de la espriella toral (born september 5, 1934) is a panamanian politician.
Example Output: ricardo de la espriella

Example Input: drift mining is a way of mining where tunnels are dug horizontally.
Example Output:
drift mining