Those are the 'plural forms', "do" and "don't"; for example when you say, "they do" or "they don't".
There are some grammatical contexts, however, in which "do" and "don't" will represent the 'singular form', such as when you are talking in first-person narrative about yourself, as in "I do" or "I don't". In that particular case the context is not plural for these same words.
(As a side note, the usual 'singular forms', outside of first-person narrative, would be "does" and "doesn't", as in "she does" or "she doesn't").
Brushes is the plural form, the singular form is brush.
I dont think there is one.
Lutz is already plural just like fish.You dont say ''look at the fishs,'' you say, ''look at the fish'' same thing with Lutz.
The plural of igloo is igloos.
There is no plural form. Do and Do not are verbs
The plural form of him, her, or it is them. (objective pronouns)
Bridges is the plural form of bridge.
The plural form of "is" is "are."
The plural form of "was" is "were."
The plural form of "I" is "we."
stupid, dont u know? Even my 5 year old sista knows that!!!
The plural form of mouth is mouths. The plural form of month is months. The Mounth is a range of hills in Scotland and does not have a plural form.