POLARITY AND EMPHASIS

POLARITY Functions of the verb DO We have earlier discussed with respect to the system of mood the special function of the operator DO in the formation of the interrogative mood. For main verbs, except for the verb BE, the simple tense interrogative is formed by the use of this operator in a split predicator.
e.g.	Do you like wine?
	Did you post the letter?
There are two other functions with which DO is similarly connected as operator in simple tenses, the determination of POLARITY which selects between positive and negative, and the expression of EMPHASIS which determines whether a verbal group is emphasised or not. We shall see that these in fact may be best understood as two sides of the same coin, for negative polarity does itself constitute a form of emphasis, and we shall refer to the system as a whole as POLAR EMPHASIS. The system selects between three contrasting features:- (i) neutral positive (non-emphatic); (ii) negative polar emphasis; (iii) positive polar emphasis. The systems of mood and polar emphasis in the simple tenses share the common feature that one choice is signified by the absence of the operator in the verbal group, while the alternative choice is signified by its inclusion. The function of the operator DO in these systems as applied to main verbs may thus be summarised as follows:-
(1)	Declarative mood and neutral positive polarity all have in common the fact that they do not incorporate the operator DO in the structure of the verbal group.

(2)	Interrogative mood, negative polarity, and positive polar emphasis all have in common the inclusion of the operator DO in the structure of the verbal group, which is instrumental in the formation of the structure.

The connection between the interrogative and polarity systems was seen also in the role of auxiliary verbs generally in signalling these structures. We saw that one of the distinguishing criteria for auxiliary verbs is the fact that unlike main verbs they form their negative by simply adding the particle "NOT" or "N'T"in postposition.
e.g.	This will not be enough.
	We aren't going.

The formation of interrogatives involves inversion of the auxiliary verb to form the split predicator.
e.g.	Has he spoken to you?

Neither of these possibilities are available to main verbs, at least in modern English.
e.g.	* Speak not of that.
	* Spoke he to you?

The above examples have a distinctly archaic sound about them, and in earlier forms of English might have been acceptable. For modern English, however, this is not acceptable usage, and as we have seen, both of these forms are now rendered by means of the operator DO. Thus we should say:-
e.g.	Don't speak of that.
	Did he speak to you?

Negative polarity, like interrogative mood, is thus expressed solely by means of an operator. If the verbal group already has an auxiliary operator then the particle NOT is placed in postposition to it. If there is no other operator, then the verb DO + NOT is added to the group, and the main verb thus takes the appropriate non-finite form. We can thus show the structure of negative polarity in the same way as we did for the structure of mood:- negative --> aux + not + v * The verb BE is of course an exception to this.
e.g.	Is he there?
	He isn't there.

Note, however, that in the imperative mood, negative polarity is formed even for the verb BE by using the operator DO + NOT.
e.g.	Don't be afraid.

The alternative sounds distinctly archaic:-
e.g.	Be not afraid.

There is of course no imperative for modal verbs, since the imperative may be formed only with the base form of a main verb.