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concentrate – v. think carefully about a specific subject
bilingual – adj. using or able to speak two languages
self-esteem – n. confidence in yourself and a belief in your qualities and abilities
frustration – n. feeling of being annoyed because things are not happening in the way that you want
input – n. ideas or effort put into an activity or process in order to help it succeed
response – n. something that is done as a reaction to something else
