An ELT Glossary : On Sentence Types

In terms of purpose, or function, sentences are generally divided into four main types :
  • Declarative
  • Interrogative
  • Exclamatory
  • Imperative
However, as we shall see, there are two problems with this classification: the first from the point of view of defining the different types, as  several categories overlap,  and the second  in terms of its inclusiveness. But let's start with some "straightforward" definitions and examples :

1. Declarative sentences serve to make a statement and primarily to convey information (Quirk et al, 1972). For example, 
  • I live in London 
  • John wasn't at the meeting. 
Notice we're talking here about function - not form. In terms of form, the statement  may be affirmative or negative.

2. Interrogative sentences serve to ask a question - ie to express lack of information and, in most cases, to request that a listener supplies it. During speech, and both the use of interrogative form and intonation can indicate this. In writing, a question mark at the end  of the sentence replaces the intonation : 
  • Where do you live? 
  • Was John at the meeting? 
  • Who said that?

3. Exclamatory sentences, as defined by Quirk et al (ibid) express the speaker's feelings. In speech they are marked by intonation and in writing by an exclamation mark. For example:
  • What a mess!
  • How sweet of you! 

4. Imperative sentences. Clear examples use the imperative form, either in the affirmative or negative. For example:
  • Put that away, please.
  • Don't forget your keys.
What Quirk et al (ibid) call the "persuasive imperative" using the dummy operator do (Do sit down), imperative with a subject (Somebody open the door / You be quiet), and the imperative with Let's (Let's go) can easily be incorporated into this function.

Some problems...

So far so good - but the first problem is that there is frequently an overlap of the functions. 

For example, many question types include a statement, ie have a declarative element. Consider tag questions :
  • You live in London, don't you?
Here, the speaker makes an initial statement which s/he is fairly sure is true, but then asks for confirmation. It is, as the name suggests, an interrogative element "tagged on" to a declarative statement. However, as it's not being used to "convey information" and there is a clear formal interrogative element, perhaps we can fit it into the interrogative category fairly easily.

Here's another example which isn't quite so easy to deal with:
  • A : I must leave by 10 or I'll miss the last train to Worcester. B: You live in Worcester?
Here, B's utterance is marked as interrogative by the intonation (or in writing the question mark), but functionally expresses B's inference of a fact - and so overlaps with the declarative function of conveying information. Quirk et al (ibid) call them "declarative questions". They also use the example of :
  • You realize what the risks are?
which, although they don't analyse it fully, seems to me interesting. Although apparently a question, used with interrogative intonation, or a question mark in writing, consider what  the speaker's purpose is here. Is it really to ask for information, or isn't it rather to convey it? There are a lot of risks, you know. This rephrasing turns it back to a declarative sentence - but there doesn't seem to me to be any real difference between the two in terms of the speaker's purpose. Remember that here we are talking about function, not form.

Similarly consider :
  1. This room is a mess!
  2. Clear this room up immediately!
  3. Can you get the room cleared up please?
  4. This room needs tidying.
Sentence 1 is apparently an exclamation, the expression of the speaker's feelings. But doesn't it also convey information? Couldn't it also be a command equivalent to the imperative of sentence 2? And isn't sentence 3 just a politer way of saying the same thing as sentence 2?  Despite the interrogative form the speaker certainly doesn't  lack information. Similarly, couldn't 4 be an implied command rather than a "declarative" statement of fact?

Then consider:
  •  James had kept things tidy, but you should have seen Paul's bedroom. It was a mess!
Although the second sentence appears to be an exclamation, the speaker is also (and perhaps principally) conveying information - so again, the exclamatory and declarative functions blend.

Similarly, in :
  • A: Open the window please. B: Open the window?! It's snowing outside!
is B's first sentence interrogative or exclamatory? And is her second sentence exclamatory or declarative?  What about :
  • What on earth does he think he's doing?
Is this a request for information? Or an exclamation?

Rhetorical questions, where the speaker or writer asks a question which he or she then proceeds to answer...
  • So what are we going to do? I think we should....
are another sentence type which don't fit neatly into the category of interrogative sentences in terms of function - the speaker is clearly not requesting information. And what about :
  • Live long and prosper
  • May you be forgiven!
  • May the force be with you.
  • Bless you
  • Wishing you all happiness
Formally the first three are imperatives, but functionally they are not commands but wishes, as is explicitly indicated in the fourth example. This type of sentence is sometimes classified as a fifth type - an optative sentence.

Which brings us to the second criticism of the classification of sentence types - the fact that the don't cover all types of sentence. Quirk et al (ibid) add a list of what they call "minor" sentence types and, as well as optative sentences, include the following (some of which I've merged), which tend to be formulaic in nature:
  • Aphorisms : The more the merrier /Easy come, easy go.
  • Greetings and farewells : Hello / Hi /Happy Christmas// Goodbye / See you.
  • Introductions : How do you do / Pleased to meet you.
  • Reactions : OK / All right / No way
  • Thanks : Thanks a lot / Ta
  • Alarm calls : Help! Fire!
  • Toasts : Cheers / Here's to your new job
  • Slogans : Down with ageism /Snap, crackle and pop (Kellogg's Rice Crispies)
  • Interjections Whew / Uh huh / Oh..
  • Expletives and Imprecations: Gosh! /Goodness /Go to hell! / Get lost.


Quirk, Greenbaum, Leech and Svartvik (1972), A Grammar of Contemporary English, Longman