The noun 'stock' is singular, a word for one stock.
The plural noun is stocks.
Note: the noun 'stock' is an uncountable (mass) noun as a word for goods or merchandise kept at a shop or warehouse.
The word 'stock' is also a verb and an adjective.
This is one of those words in English that the single and plural is the same word.
The noun 'onlooker' is a single compound word, the plural is onlookers.
The last word lol
The plural form of the noun ''country'' is countries.
Actually both of the answers below are correct - if you're talking about a single kind of ammunition, then the word could be both singular and plural. If you're talking about several kinds of different ammunition, the plural is ammunitions.
Single
The word Christmas is singular; the plural form is Christmases.
If there is no single significant word in a compound word, add the plural ending to both parts of the compound word.
The noun 'onlooker' is a single compound word, the plural is onlookers.
This is one of those words in English that the single and plural is the same word.
The noun 'onlooker' is a single compound word, the plural is onlookers.
If there is no significant word in a compound word, you can add the plural ending directly to the last word in the compound.
strenua (single) strenuae (plural)
No, feet is plural. Foot is singular.
The last word lol
stocking is translated "bas" (masc.) The spelling is the same for singular and plural. The final 's' is unvoiced.
A stocking is 'un bas' in French.