Упражнение № 6 Поставьте существительные в скобках в правильном числе: More than one (day); twenty-one (day); a (pair) of shoes; two (pair) of shoes; four (dozen) buttons; the variety of (fish) in the aquarium; the Russian (people) are very hospitable; you must eat more (fruit); our (family) are all good chess-players.