'Negligence' is an abstract noun and does not take a plural form. You could refer to 'several instances of negligence' or 'numerous examples of negligence' or 'many types of negligence', or similar constructions, but you would not say 'several negligences'.
The plural form for the demonstrative pronoun this is these.
The plural form of the word "inferno" is "infernos."
The plural form of the word "ranch" is "ranches."
There is no plural form for the word, countries. This word itself is a plural.
There is no plural word for if.
The plural form is data.
The plural form of the word "baby" is "babies."
The plural form of vow is vows.
The plural form of the word "pharynx" is "pharynges."
The plural form for the word 'pioneer' is pioneers.
In Chinese, the plural form of the word "minute" is "分钟" (fēnzhōng).
The plural form for the noun valley is valleys.