we can divide nouns into two groups;
1- countable
2- uncountable
we cant make plural uncountable nouns, e.g. water,milk etc..
when we look at countable we see there are four rules to make them plural;
1-s
2-es
3-ies
4-ves
a countable noun ends with ;s,ss,sh,ch,x,o PLUS es: watch-watches
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