VOA慢速英语:European, US Officials Warn of Terror Threat

defector – n. a person who leaves a country, political party, or organization and goes to a different one that is a competitor or an enemy

extremist – n. someone who has extreme ideas about politics, religion, etc.

initial – n. occurring at the beginning of something

sanction – n. an action that is taken or an order that is given to force a country to obey international laws by limiting or stopping trade with that country by not allowing economic aid for that country

zero-tolerance – n. a policy of giving the most severe punishment possible to every person who commits a crime or breaks a rule