Great Photographs from the US Library of Congress

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collect/collection - v. to bring or gather together in one place; to demand and receive (“collect taxes”)

iBook - n. an electronic book that can only be read using Apple Computer company devices

eBook - n. an electronic book that can be read on a computer or other electronic devices

difficult - adj. not easy; hard to do, make or carry out

complain - v. to say or write that you are unhappy, sick, uncomfortable, or that you do not like something