This section is from the book "Two Years' Course In English Composition", by Charles Lane Hanson. Also available from Amazon: Two Years' Course In English Composition.
The different manners ("modes") of expressing the thought of the verb are called moods.
1. John works. (A fact, - indicative mood).
2. I wish John were working. (A wish, an unreality, not a fact, - subjunctive mood).
3. Work. (A command, - imperative mood).
The indicative mood asserts a fact, or something assumed to be a fact, or asks questions of fact.
We saw him. Doubtless he is here. Does he study hard ?
The subjunctive mood presents doubtful or conditional assertions, or unrealities.
If you were to ask him, he would grant the request.
If this charge be proved against him, he will suffer for it.
If he were here, we could see him. (Present condition contrary to fact).
If he had not been here, I should have telephoned for him. (Past condition contrary to fact).
The imperative mood expresses a command, an entreaty, or a wish.
Go! Let us try.
240. Explain the value of the subjunctive mood in each of these sentences:
1. If there be any difference, the former are rather the more substantial.
2. Were he still a writer, and as brilliant a one as ever, he could no longer maintain anything like the same position in literature.
3. Were it only possible to find out who are alive and who dead, it would contribute infinitely to my peace of mind.
4. If he have strength of arm, well and good; it is one species of superiority.
241. In the following sentences, insert the correct form of the verb, tell what mood is used, and justify your choice:
1. If I (be) rich, I should know what to do.
2. If he (look) with care, he will find his cap.
3. You may tell him to come if he (have) the time.
4. I am not certain that he (give, present perfect) the matter much thought.
5. If you actually (tell) him, why did he not send a reply ?
6. If the ball (give, passive) to the child, he will remain quiet.
7. I am sure that he (go) by the house a few moments ago.
8. Shut the door if you (feel) a draft.
9. You must remain quiet if you (wish) to hear the music.
10. Even (be) he to come now, he would be too late to catch the train.
 
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