In the sense of "toast," health could be pluralized, as in "We drank so many healths we got sick." Otherwise, it has no plural.
Bills of health is the plural
Bridges is the plural form of bridge.
"Beliefs" does not have a plural form, as it is already plural. Beliefs is the plural form of belief.
The plural of board is boards.
There is no plural form for the word, countries. This word itself is a plural.
Health is an uncountable noun and has no plural.
The plural form for the noun chicken is chickens; the plural possessive form is chickens'.
There is no plural form. Do and Do not are verbs
Bills of health is the plural
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."
"Groceries" is the plural form of "grocery."
"Beliefs" does not have a plural form, as it is already plural. Beliefs is the plural form of belief.
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.