"Biopsy" is the singular form, while "biopsies" is the plural form.
singular
biopsies
"My Father had a biopsy to make sure the lump was not cancerous"
"The BIOPSY revealed scar tissue."Merrium-Webster Dictionary
The first syllable of biopsy is accented.
The word crises is a plural word; it is the plural form of the word crisis.
The doctor took a biopsy of a growth on the patients leg and sent it to the lab for analysis.
There is no plural word for if.
The plural word for delay is delays.
A non-plural word, a word (noun or pronoun) that is not plural is singular, a word for just one.
the plural word is comedones