It is the singular possessive form of the noun coaster (inanimate possessive).
Example: The coaster's cork bottom became stuck to the table.
Are is plural. "Is" is singular. For example, "There is a glove on the chair". That is singular. "There are gloves on the chair". That is plural.
Who may be singular or plural.
diagnosis is singular diagnoses is plural sis = singular ses = plural
Atrium is singular - the plural is atria.
Statistics is plural, the singular form is statistic.
Coaster's is singular possessive. The plural is coasters, the plural possessive is coasters'.
practitioner is singular (plural practitioners)sofa is singular (plural sofas)satellite is singular (plural satellites)clips is plural (singular clip)dentist is singular (plural dentists)dollars is plural (singular dollar)article is singular (plural articles)magazines is plural (singular magazine)laminator is singular (laminators is plural)radios is plural (singular radio)
singular and plural
Singular: book / Plural: books Singular: cat / Plural: cats Singular: child / Plural: children Singular: foot / Plural: feet
Are is plural. "Is" is singular. For example, "There is a glove on the chair". That is singular. "There are gloves on the chair". That is plural.
"Has" is singular, e.g. He has, she has. "Have" is plural, e.g. They have, we have. The exception is "I" - e.g. I have.
The word team is singular; the plural form is teams.
'These' is the plural form of 'this'.
Who may be singular or plural.
This is singular. These is the plural form.
These is plural, this is singular
"Notebook" is singular. The plural form is "notebooks."