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tanker – n. a huge ship, truck or airplane specially made to carry materials such as oil or fuel
enrichment –n. to increase the quality of something or increase its usefulness
countdown –n. a period of time before an important event takes place: such as a launch or reaching a goal
reserve –n. a supply of something to be used at a later time
commercial –adj. related to buying or selling goods
navigation –n. the act of moving a boat or ship over an area of water
role –n. the part someone or some group plays in an event or situation
