The word population is a noun. The plural is populations.
Population is singular. Populations is plural.
The word crises is a plural word; it is the plural form of the word crisis.
There is no plural word for if.
The word 'graphs' is the plural noun.The singular noun is 'graph'.Examples:We've compiled all of the graphs in one file. (plural)This graph shows the growth rate of population. (singular)The word 'graphs' is also the third person, singular, present of the verb to graph.
The plural form for the demonstrative pronoun this is these.
A non-plural word, a word (noun or pronoun) that is not plural is singular, a word for just one.
The plural word of delay is delays.
the plural word is comedones
No it's a singular word. A plural word would be "have".
Leukocytes is the plural of leukocyte
The plural of "classification" is "classifications."