变化规律是:
1、直接加s 例如ruler-rulers, pen-pens
3、以s, x, sh, ch, 结尾加es. 例如bus-buses, box-boxes,
watch-watches,
例如photo--photos, zoo--zoos, piano--pianos (小学记住这7个单词就行)
5、辅音字母加y,改y为i加es.例如family-families, library-libraries
strawberry, company, country,这三个也是要改y为I加es的。你会改吗?



