The plural form of the word zero is zeroes, like "There are a lot of zeroes in that number."
There is no plural form for the word, countries. This word itself is a plural.
The plural form is data.
The plural form is hostesses.
The word "police" is plural and it takes a plural verb.
The plural form of the word "perseverance" is "perseverances."
The plural form of phylum is phyla.
Just add -es to make aliases.
The plural of diagnosis is diagnoses
The plural form for alumnus is alumni.
The plural of fossil is fossils.
The plural form of the word man is men.
The plural of ambulance is ambulances.