One group of words that have no singular form are aggregate nouns, words representing an indefinite number of parts; aggregate nouns have no singular form. Examples:
Another group of nouns are the binary nouns, words for things that are two parts making up the whole, they are a shortened form for 'a pair of', for example:
Some words ending in o that form their plural by adding s only include: pianos, duos, solos, tacos.
There is no plural form. Do and Do not are verbs
The usual plural form for words ending in -f or -ef is to drop the f and add ves. There are exceptions to this rule where only an s is added to the end of the words.
The plural of lunch is "lunches" No words form the plural lunch as it isn't a plural itself
No, not all words have a distinct plural possessive form. Some singular possessive forms can be used to indicate possession for both singular and plural nouns. For example, "children's" can be used for the plural possessive of "child" and "children."
The only possible plural form of "it is" would be "they are".
There can be no plural form of to. To is a preposition. there can only be plural forms of nouns.
The plural is "journeys". Unlike words ending in Y, the -ey words mostly form normal S plurals.
The plural of address is addresses and the plural possessive is addresses' (apostrophe only).
The plural is schools. The plural possessive form is schools' (apostrophe only).
There is no plural form, not all words can be plural, and thus ends up being 'and'.
the plural form of words ending in ss, like kiss, is just adding es (kisses) (sorry, kiss was the only word ending in ss i cud think of)