Compound forms, auxiliaries and modals

The auxiliary and present subjunctive do is rarely used, perchance as an emphatic form.^[1] As a present subjunctive, it is identical to the bare infinitive, is accompanied by a bare infinitive (except be, which cannot be used with do -support in either the indicative or subjunctive mood) and can usually be recognized only with the third person singular. For example:

· (that) I do own, (that) you do own, (that) he do own, (that) we do own, (that) they do own

Although it is possible to use this auxiliary for negation, it is never mandatory to do so and is frequently seen as ambiguous or incorrect because of its resemblance to the indicative. The negated present subjunctive is always unambiguous with the third person singular (e.g., (that) he do not own).

The auxiliary and past subjunctive did, when not used for negation, is somewhat more frequent as an emphatic form and is conjugated the same as the indicative (e.g., (that) I did own).

Occasionally, a present perfect subjunctive is seen, as in It is important that he have completed two years of Spanish before graduation. ^{[ citation needed ]}

A compound past subjunctive form is made with were (the past subjunctive of be) followed by a verb's to-infinitive (corresponding to indicative forms like I was to own). For example:

· (if) I were to own, (if) you were to own, (if) he were to own,...

A pluperfect subjunctive may be considered to exist; its form (had with past participle) does not differ from the corresponding indicative, but a distinction can be sought in the possibility of inversion: had I sung... (equivalent to if I had sung). A compound pluperfect subjunctive can be formed with were followed by to have and the verb's past participle; consequently, the previous example can be expressed as such: if I were to have sung. ^{[ citation needed ]}

The English modal verbs do not have present subjunctive forms, except for synonyms such as be able to as a subjunctive corresponding to the indicative modal can. However would, should, could and might can in some contexts be regarded as past subjunctives of will, shall, can and may respectively. (They may also be described simply as the past forms of the latter modals, or as modals or auxiliaries in their own right.)

The auxiliary should is used to make another compound form that might be regarded as a subjunctive, and, in any case, it is frequently used as an alternative to the simple present subjunctive. For example:

· With present subjunctive: It's important that he be cured.

· With should: It's important that he should be cured.

The should form, in certain conditionals, can undergo inversion as described below.

2. Formation of the subjunctive
The English past and present tenses discussed in previous chapters are in what is usually referred to as the Indicative Mood. Each of the past and present tenses in the Indicative Mood has a corresponding tense in the Subjunctive Mood.
In modern English, most verb tenses in the Subjunctive Mood are similar or identical to the corresponding tenses in the Indicative Mood. It should be noted that verbs in the Subjunctive Mood do not modify, but have the same form regardless of the subject.

The Simple Present Subjunctive and Simple Past Subjunctive of the verb to be are shown below. The Indicative forms are also given, for purposes of comparison. The Subjunctive forms which differ from the corresponding Indicative forms are shown in bold type.

The simple indicative and subjunctive tenses of the verb To Be
Simple Present

Simple Past

For any verb, the Simple Present Subjunctive is formed from the bare infinitive of the verb.
For any verb except the verb to be, the Simple Past Subjunctive is identical to the Simple Past Indicative.
For all of the past and present tenses conjugated with auxiliaries, the Subjunctive tenses are formed in the same way as the Indicative tenses, except that the Subjunctive of the auxiliaries is used.
Using the example of the verb to work, the following table compares the tenses of the Indicative and Subjunctive Moods. The Subjunctive forms which differ from the corresponding Indicative forms are printed in bold type.