Problem: What are the most important words?
troops arrive at their barracks to reinforce fellow troops following the siege by militants
Answer: arrive, barrack, militant, reinforce, troop


Problem: What are the most important words?
police officers take an oath of office during swearing in ceremony
Answer: ceremony, oath, officer, swear


Problem: What are the most important words?
military vehicle patrolling the border
Answer:
border, patrol, vehicle