VOA慢速英语:Tensions Increase Between North and South Korea

psychological - adj. of or related to the mind

conduct – v. to plan and do (something, such as an activity)

brag – v. to talk about yourself, your achievements, your family, etc., in a way that shows too much pride (often + about)

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

billboard – n. a large sign for advertisements that is next to a road, on the side of a building, in a sports center, etc.

sanctions – 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, etc. (usually plural)

business-as-usual – expression used to say that something is working or continuing in the normal or usual way

provocation – n. an action or occurrence that causes someone to become angry or to begin to do something

reluctant – adj. feeling or showing doubt about doing something; not willing or eager to do something