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voucher – n. a document that gives you the right to get something (such as a product or service) without paying for it
survey – n. an activity in which many people are asked a question or a series of questions in order to gather information about what most people do or think about something
sour – v. to become unpleasant or unfriendly
discourage – v. to make (someone) less determined, hopeful, or confident
partisan –adj. strongly supporting one leader, group, or cause over another
alienate – v. to make (someone) unfriendly : to cause (someone) to stop being friendly, helpful, etc., towards you
