Atrium is singular - the plural is atria.
Atria is plural for Atrium. You have your (rt)Atrium and (lt)Atrium
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
Statistics is plural, the singular form is statistic.
Atria is plural for Atrium. You have your (rt)Atrium and (lt)Atrium
The Atria and Atrium
the upper chambers of the heart are called the atria. (or atrium singular)
The plural is atria. This can be used architecturally or with reference to chambers of the heart.
Atria is the plural for of atrium. Not the other way around.
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.
Who may be singular or plural.