Japan, South Korea Warn Against North Korea Missile Launch

grave – adj. very serious; requiring or causing serious thought or concern

provocative – adj. causing discussion, thought, argument, etc

unit – n. a single thing, person or group that is a part of something larger

cascade – n. a large number of things that happen quickly in a series

effect – n. a change that results when something is done or happens; an event, condition or state of affairs that is produced by a cause

consequences – n. something that happens as a result of a particular action or set of conditions

defect – v. to leave a country, political party, organization, etc., and go to a different one that is a competitor or an enemy