英语单词单复数

Map- boy- girl- pen-

bag- car- bus- watch-

box- brush- baby--- city- country- monkey--- holiday--- photo--- piano--- radio--- zoo--- potato-- tomato--

belief--- roof--- safe--- gulf--- half--- knife--- leaf--- wolf--- wife--- life--- thief---

child---children foot---feet tooth---teeth mouse---mice man---men woman---women

单复同形，如deer，sheep，fish，Chinese，Japanese