The plural form of thumb is thumbs.
The plural form of the demonstrative pronoun 'that' is those.
The plural form of rung is rungs.
The plural form of parenthesis is parentheses.
The plural form of boy is boys.
The plural form of "viola" is "violas."
Rules of thumb
The plural of the English word "prize" is prizes.Example:"Sarah, a gifted equestrian, has won many prizes at horse shows."
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.
There is no plural form for the word, countries. This word itself is a plural.
"Groceries" is the plural form of "grocery."
The plural form of "meter" is "meters."
The plural form for the noun sergeant is sergeants; the plural possessive form is sergeants'.
It has no plural form.
The plural form of rung is rungs.
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.
The plural of "she" is "they", so the plural of "she had" is "they had".