The word "rare" is an adjective and does not have a plural form. Adjectives in English do not change to indicate singular or plural; instead, they modify nouns that can be pluralized. For example, you would say "rare items" to refer to multiple rare things.
The plural form of the noun phenomenon is phenomena.The plural possessive form is phenomena's.Example: These phenomena's occurrences are very rare.
The plural of calculus is generally "calculi." The word "calculuses" is also a plural, but very rare.
ALGAE is the plural form, commonly used in place of the singular ALGA because references to a single organism are rare.
Mississippi is singular. Since there is only one state and one river by that name, it would be rare to have need of a plural form.
The Plural for moose is moose.Examples:Look at that moose! (singular)Look at all those moose! (plural)
In American English, it is extremely rare for a plural word to end in a letter outside of "S".
That is the correct spelling of the plural noun "pandas" (type of rare bear).
The plural of Nike (shoe) would be Nikes. Except in rare cases, apostrophes are not used to form plural nouns. The form Nike's would mean something about Nike.
Both the singular and plural future tense are "will jump." "Shall jump" is another option, although this is relatively rare in American English in the sense of a true future tense.
The word "enjoy" is a verb and does not have a plural form in the same way that nouns do. However, when referring to multiple subjects who enjoy something, you might say "they enjoy" or "we enjoy." In contexts where "enjoy" is used as a noun (though rare), the plural could be "enjoys," but this usage is not common.
Domesticated pigs are kept in a sty (or stye (very rare)), the plural of sty is (according to OED, Chambers and Merriam-Webster) sties or alternatively (according to Chambers and Merriam-Webster) styes.
3. This is a rare word in English which uses a 2 plural morphemes. 1.Child- 2. -r- 3. -en -en is a rare (but not completely uncommon) plural morpheme. We see it in words like oxen. The -r- suffix was also used in middle English but only survives in this word, unless I am mistaken.