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tunnel - n. an underground passageway
smuggle - v. to illegally transport drugs or people
drug traffickers - n. criminals who transport illegal drugs
financier - n. a person or group that provides money for projects
light at the end of the tunnel - expression hope of success, happiness or help after a long period of difficulty; sign of improvement in a situation that has been bad for a long time
prefer - v. to like (someone or something) better than someone or something else
clay - n. heavy, sticky dirt or earth
