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source – n. someone or something that provides what is wanted or needed
perplexing – adj. difficult to understand : causing confusion
confusing – adj. to make (something) difficult to understand
tough – adj. difficult to accomplish, resolve, endure, or deal with
riddle – n. a puzzling question to be solved or answered by guessing
enigma – n. something hard to understand or explain
intention – n. the thing that you plan to do or achieve : an aim or purpose
forecast – v. to say that (something) will happen in the future : to predict (something, such as weather) after looking at the information that is available
key – n. something extremely important
