Uses of the Subjunctive.—The indicative form is used in expressing a fact or what is assumed to be a fact: as "He thinks he is ill;" the subjunctive form indicates some uncertainty or doubt in the speaker's mind: as, "Whether it rain or not, I will go."
The subjunctive idea occurs most frequently, perhaps, in conditional sentences. A conditional sentence is one that contains a condition or supposition. A supposition may refer to present, past, or future time. If it refers to present or past time, it may be viewed by the speaker as true, untrue, or as a mere supposition with nothing implied as to its truth; if it refers to the future, it may be viewed as either likely or unlikely. A supposition which is assumed to be true, or which is made without any hint as to its correctness, is expressed by the indicative. A supposition which is viewed by the speaker as untrue or unlikely is expressed by the subjunctive or a periphrase[87] for the subjunctive. When the character of the supposition makes the conclusion untrue or unlikely, the conclusion also is expressed by the subjunctive or a periphrase[87] for the subjunctive. The use of tenses is peculiar, as will be seen from the following table of a few common forms of conditional sentences. The tenses should be carefully noted:—
| P R E S E N T |
If it rains (is raining) now, I am sorry. Present indicative: A simple supposition without any hint as to its correctness If it rained (were raining), I should be sorry. Past subjunctive, both clauses: The speaker implies that it is not raining. |
| P A S T |
If it rained (was raining), I was sorry. Past indicative: No suggestion of doubt. If it had rained, I should have been sorry. Past perfect subjunctive, both clauses: The speaker implies that it did not rain. |
| F U T U R E |
If it rains, I shall be sorry. Present indicative: The common, though inexact, form of a simple future supposition. If it rain, I shall be sorry. Present subjunctive: Less common, but more exact. The future is uncertain. If it should (were to) rain, I should be sorry. Subjunctive, both clauses: The uncertainty is emphasized by the auxiliary form; the chances of rain seem more remote. |
NOTE 1.—When if is equivalent to "whenever", the condition is called "general", to distinguish it from "particular" conditions, which refer to some particular act at some particular time. General conditions always take the indicative: as, "If (whenever) it rains, I stay at home."
NOTE 2.—Sometimes there is no "if", and then the verb or a part of the verb precedes the subject: as, "Were it raining, I should be sorry;" "Had it been raining, I should have been sorry."
NOTE 3.—In such sentences as "If thou hadst been here, my brother had not died," it may perhaps be questioned whether "had not died" is indicative, as in the Greek, or subjunctive, as in the Latin, idiom.
NOTE 4.—Clauses introduced by though and unless take the same forms as clauses introduced by if.
Wishes are naturally expressed in the subjunctive. The present subjunctive denotes a wish for the future: as, "Thy kingdom come." The past subjunctive denotes a wish for the present which is unfulfilled: as, "I wish I were a bird." The past perfect subjunctive denotes a wish contrary to a past fact: as, "I wish you had been there."