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module – n., a part of a computer or a computer program that can be combined or completed to build something
convenient – adj., allowing you to do something easily and without trouble
prefer - v., to like (someone or something) better than someone or something else
interactive - adj., involving the actions or input of a user; especially: of, relating to, or being a two-way electronic communication system (as in a telephone, cable television, or a computer) that involves a user's orders
mathematics - n., the science of numbers, quantities and spaces and the relationship among them
practice - v., to do something again and again in order to become better at it
