Hard core consists of pieces of broken stone that are used as a base on which to build roads. (mainly BRIT)
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Hard core consists of pieces of broken stone that are used as a base on which to build roads. (mainly BRIT)
N-UNCOUNT
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012