An interrogative sentence ends with a question mark rather than a period. In most cases, an interrogative sentence classifies as a direct question because it requires an answer. This specific type of sentence seeks confirmation, approval, or denial of something, as well as basic information. The main types of interrogative sentences include “Wh” questions, yes/no questions, and tag questions.
The most common interrogative sentence begins either with “Wh” question words, which attempts to acquire some information. These question words include “What, “When,” “Why,” as well as “Where,” “Who,” and sometimes “How.” Some examples of “Wh”-based questions include, “What time is it?” and “When is your vacation?” Others can include "Who is it?", "Why did you do that?", and "How was your day?" These types of questions usually include a helping verb such as "do" or "be" to indicate the present state or condition, and answers to these types of interrogative sentences may be simple or open-ended.
Another type of interrogative sentence requires a simple "yes" or "no" response, or alternatives that allow for the respondent to give multiple answers or make a choice. Like a "Wh" question, a yes/no interrogative sentence can also include a helping verb. Examples of everyday questions that apply the yes/no interrogative include: "Did you go to the store?" and "Are you ready to go to the basketball game?" Alternative yes/no questions may include, "Do you want cereal or oatmeal?" and "Would you prefer to go to the beach or the zoo?"
A tag question turns a declarative sentence into an interrogative one. A declarative sentence illustrates a statement or fact with no response required, but it can become an interrogative when a person attaches a question at the end rather than a period. The new sentence often requires a response when transformed from declarative to interrogative. "The weather is nice today, isn't it?" and "You're coming to the class reunion, aren't you?" are some examples of tag questions. A direct, interrogative tag sentence forms when the verb comes before the subject in the sentence and ends with a question mark.
Depending on how the person writes or speaks it, a tag question may still qualify as a declarative sentence, but with a question mark at the end. This type of tag question often follows a rising intonation pattern. For instance, "You've finished your homework already?" and "The Mavericks won the NBA championship?" illustrate examples of tag questions spoken with a rising intonation at the end of the sentence. The tag question-based interrogative sentence generally confirms an idea or a true statement when in doubt.