e.g果o的唔可以再寫
No.1 singular nouns (e.g.bird,pen) (10個)
No.2 plural nouns(e.g.bird) (10個)
No.3 some nouns are always plural(e.g.scissors) (7個)
No.4 some nouns are plural but without 's' or 'es' (5個)
No.5 some nouns have the same form for sigular and plural (e.g.fish) (5個)