Interrogative sentences are of two kinds:
1. Those that can be answered by yes or no,—“Can a man weigh off and value the glories of dawn against the darkness of hurricane?”—De Quincey.
These sentences put in question the whole thought, and are usually in the inverted order, the auxiliary of the predicate verb coming before the subject.
2. Those that cannot be answered by yes or no,—“Why should the trees be so lovely in Japan?”—Hearn.
These sentences put in question only one point, either the subject, the object, an attribute of the subject or object, or some circumstance of time, manner, place, cause, etc. They usually begin with an interrogative word, such as the pronouns who, which, what, or the adverbs how, when, why, where.
Interrogative sentences have sometimes the same order and arrangement of words as declarative sentences. It is only by hearing them spoken or noting their punctuation that we know they are interrogative; for example, “Scrooge knew he was dead?”—Dickens. This is equivalent to—“Did Scrooge know that he was dead?”
Before analyzing an interrogative sentence, its order, if inverted, should be changed to that of the declarative sentence. Motley’s question,—“When did one man ever civilize a people?” becomes for analysis,—“One man did ever civilize a people when?” Notice that the time of an action is the point in question here, and the desired answer will be this very same sentence with only two changes, the omission of ever and the substitution of a word or phrase signifying a definite time, for the word when.
The Imperative Sentence.—An imperative sentence is one that conveys a command,—“Tell me why you have brought me to this place.”—Caine.
The command is frequently so mild that it becomes more a request or piece of advice,—“Speak as you think, be what you are, pay your debts of all kinds.”—Emerson.
Sometimes it is even an entreaty,—“Give us this day our daily bread.”