可数名词：表示可以具体个别存在的人或物。可数名词有单复数形式，其单数形式与不定冠词a(n)连用。
可数名词复数规则：
1.一般情况下，直接加-s，如：book-books, bag-bags, cat-cats, bed-beds
2.以s. x. sh. ch结尾，加-es，如：bus-buses, box-boxes, brush-brushes, watch-watches
3.以“辅音字母+y”结尾，变y为i, 再加-es，如：family-families, strawberry-strawberries
4.以“f或fe”结尾，变f或fe为v, 再加-es，如：knife-knives
5.不规则名词复数：
man-men, woman-women, policeman-policemen, policewoman-policewomen, mouse-mice
child-children
foot-feet, tooth-teeth
fish-fish, people-people, sheep-sheep, chinese-chinese, japanese-japanese
不可数名词：表示不能个别存在的事物，如液体类，气体类的物质；少数固体类的物质 （grass草，ice冰），抽象的名词（help帮助，music音乐）。不可数名词没有复数（如some water）,不能与不定冠词连用。
写出下列各词的复数
diary ____________ day_____________ dress _______________ glass __________
peach___________ juice________________water ____________ rice______________
tea ______________ man____________ woman____________ banana ___________ bus___________ child ____________ foot _____________ sheep ____________ leaf(树叶) ________ dish ____________ knife _____________ pen____________ boy__________ baby___________ map _____________ city ____________ box __________ book ___________ class ____________ eye ____________ office ________ car____________ fox(狐狸) ___________ watch ____________ library ________ pear ___________ skirt ____________ shelf _____________ tomato _________tooth ____________ englishman________ paper __________ milk___________ family __________ mouse __________ people (人们) __________ fish _________ brush ________ japanese ____________ policeman____________ watermelon______________ chinese____________ strawberry _________ match ____