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has bought had bought buys has had
when did he buy the book where did he buy the book when he bought the book where he bought the book
bought, bought bought, buy had, bought had, have bought
bought, bought bought, buy had, bought had, have bought
Losing Lost Having lost To be lost
bought; paid spent; took paid; spent bought; cost
read; back to bought; to borrowed; back to kept; to
bought to buy buying to be bought
borrowed lent kept bought