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proficiency –n. the ability to do something well
sophistication –n. having a lot of experience and knowledge about a subject such as technology or art
tanker - n. ship that is designed to carry liquid, like oil
drone - n. small aircraft that flies without a pilot
enrichment - n. process of increasing natural uranium for nuclear use
sanction - n. action taken to force a country to obey international laws by limiting or stopping trade with that country
