kind of

kind of, sort of

1. These expressions mean much the same, and share the same grammatical problems. (The issues raised here seem to occur less often in practice with the third alternative, type of.) There is less of a problem when kind of is preceded by a or the, which are invariable, but difficulties arise with this, that, these, and those. When followed by a singular noun, the correct form is (e.g.) this kind [or sort] of house, not this kind [or sort] of a house. When it is followed by a plural noun, many purists insist on making kind or sort plural as well, e.g. these kinds [or sorts] of houses. To say this kind [or sort] of houses is ungrammatical, but an alternative style these kind [or sort] of houses has been in use since the 14c. Although this too is ungrammatical on a normal interpretation and was questioned by the OED, its rationale lies in regarding kind of as an adjectival phrase qualifying the following noun (in this case, houses), with the demonstrative pronoun these or those also qualifying houses rather than qualifying kind (or sort). This type is now very common in colloquial contexts:

• She was used to these kind of smells in the night-time bedclothes —M. Duckworth, 1960

• These sort of people are only interested in lining their pockets —J. Leland, 1987

• We can't let these sort of people get away with it —Birmingham Post, 2007.

Alternatives are these kinds (or sorts) of —and —of this kind (or sort):

• The pressure here is to consider the…circumstances which do, in fact, coerce people in these sorts of ways —M. Whitford et al., 1989

• Conservatives can be every bit as ideologically lethal as liberals when ballots of this kind are placed in their hands —White House Studies, 2003.

The second of these alternatives suits a context in which another modifying word is present (future in the following example):

• The decline of letter-writing makes future books of this sort unlikely —New Zealand Listener, 2003.

2. In AmE, kind of a is often used informally where in BrE it would be a kind of:

• We're kind of a middle-aged Sonny and Cher —Washington Post, 1973.

3. Kind of and sort of also occur as adverbial phrases in informal contexts, especially in AmE:

• All these rich bastards driving up the property values have kind of made it impossible for everyone else —New Yorker, 1987

• He just sort of glanced at the photos and then carried on talking —N. Watts, 1990.

4. The uses shown in paragraphs 2 and 3 are characteristically American and should not be used in more formal speech or writing. An even more informal written form is kinda, which represents the sound of kind of in rapid speech:

• That little chap must have been really desperate to take that kinda crap —Caris Davis, 1989

• There was this real weirdo in here, rifling about the desks, wearing some kinda disguise —S. James, 1993

• I feel kinda bad for not being as excited as I should be about Audrey getting into NYU —fiction website, AmE 2004 [OEC].

Again the association is chiefly American, and although it is non-standard it is extremely common, with around 20,000 examples in the OEC.