- Two types of user are identified.
- Two types of users are identified.
Both of them are correct sentence. They both can be used in formal and informal style. kinds/sorts/types are followed by both singular or plural nouns. I noticed that "two types of user" is more common in BrE, than AmE; AmE prefers "two types of users".
The following constructions are possible -
i) These/Those kinds/types/sorts of [(singular or plural form of countable noun) or (uncountable noun)]
ii) These/Those kind/type/sort of [(singular or plural form of countable noun) or (uncountable noun)] [INFORMAL]
iii) All/two kinds/types/sorts of [(singular or plural form of countable noun) or (uncountable noun)]
iv) This/That kind/type/sort of [(singular form of countable noun) or (uncountable noun)]
v) This/That kind/type/sort of [(plural form of countable noun)] [Most people think it unacceptable, better be avoided]
vi) This/That kind/type/sort of a singular form of countable noun [INFORMAL]
For details, see below -
When it’s this type of, the word following is normally singular, as in
this type of accident/game/garden/sausage. The corresponding plural
phrase: these types of is much less common in both American and
British English, by a factor of 1:7 in CCAE and 1:10 in the BNC. These
types of takes both plural and singular nouns following, as in these
types of drama and these types of plays. The compromise form these
type of is rare in both databases, and mostly found in speech. Some
uses such as these type of things show it as a routine pause filler,
but others are deliberate: these type of games/links/specials/
Source - The Cambridge Guide to English Usage by Pam Peters
Partitive constructions -
Both count and uncountable nouns can enter partitive constructions,
i.e constructions denoting a part of a whole. such constructions
express both quality partition (eg: a kind of paper) and a quantity
partition (eg: a piece of paper). Quality partition is expressed by
a partitive count noun like kind, sort, or type followed by an
- a) a new kind of computer [SINGULAR PARTITIVE]
- b) new kinds of computers [PLURAL PARTITIVE]
- a) a delicious sort of bread [SINGULAR PARTITIVE]
- b) delicious sorts of bread [PLURAL PARTITIVE]
- a) another type of research [SINGULAR PARTITIVE]
- b) other types of research [PLURAL PARTITIVE]
But in informal context, the following is also acceptable -
These/Those sort/kind/type of parties are dangerous. [INFORMAL]
Source - A Comprehensive Grammar of English Language by Randolph Quirk, Sidney Greenbaum, Geoffrey Leech, and Jan Svartvik (Page No. 249 and 764) ENTRY 10.43
The words kind, sort, and type can be troublesome when they are
used with plural nouns and modifiers. Sentences like I hate these
kind of movies may occur with some frequency but are awkward, and
some would say, grammatically incorrect. The Usage Panel frowns upon
these usages. In our 2005 survey, 81 percent rejected the use of
kind with a plural modifier and plural noun in the sentence Those kind of buildings seem old-fashioned. Fully 88 percent of the Panel
found unacceptable the use of kind with a singular modifier and
plural noun and verb in That kind of buildings seem old fashioned.
In these examples kind would presumably function as a determiner
like number in A great number of people have crowded into the
lobby. (Note that number here is singular, but the plural verb
have agrees with the plural noun people, so number is not really the subject of the sentence). This problem can be avoided by making
the phrase entirely singular (as in That kind of movie is always
enjoyable) or by revising so that the noun is the plural subject (as
in Movies of that kind are always enjoyable). Bear in mind that
plural kinds often implies that the phrase refers to a number of
different categories of things—more than one genre of movie, for
example. Perhaps the best solution is to drop the kind phrase
entirely (Those movies are always enjoyable) or to be specific
(Those spy movies are always enjoyable).
Source - Usage Note from The American heritage Dictionary Of
the English Language
Kind, sort and type are countable nouns.
Source - Macmillan Dictionary
As they are countable noun, after words like all, many, two etc. we use kinds, not kind. We don't say All kind of ..., to make it correct we use All kinds of ...
The article a/an is usually dropped after sort of, kind of and
type of, but structures with articles are possible in an informal style:
That's a funny sort of (a) car.
What sort of (a) bird is that?
When we are talking about one sort of thing, we can use sort of, kind
of or type of followed by a singular noun.
This sort of car is enormously expensive to run.
I'm interested in any new type of development in computer science.
Singular sort of, kind of and type of can also be followed by
plural nouns, especially in an informal style:
I'm interested in any new kind of developments.
Plural demonstratives (these and those) can also be used:
Those sort of cars are enormously expensive to run.
Do you smoke those kind of cigarettes?
This structure is often felt to be incorrect, and is usually avoided
in a formal style. This can be done by using singular noun (see
above), by using plural sorts/kinds/types, or by using structure
...of this/that sort/kind/type:
This sort of car is ...
These kinds of car(s) are ...
Cars of that type are ...
Source - Practical English Usage by Michael Swan