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: silliness is when a person acts like a fool, or shows a lack of good sense or judgment.

SOLUTION: silliness

PROBLEM: leslie grantham (30 april 1947 15 june 2018) was a british actor and convicted murderer.

SOLUTION: leslie grantham

PROBLEM: the russian ground forces (russian: ) are the land forces of the armed forces of the russian federation, formed after the break up of the soviet union.

SOLUTION:
russian ground forces