“Yikes,” “Oh no” and “Holy cow!” are all interjections because they convey only meaning or feeling and do not have a grammatical relationship with the rest of the sentence or contribute to the reader’s understanding of relationships between the sentence’s other words and phrases. Some interjections, such as “Yes,” “No” or “Indeed,” become different parts of speech when used in different contexts, while other interjections, such as “Ouch!” and “Whoops,” never convey meaning beyond the emotion they express.
Interjections are often offset by a comma or followed by an exclamation point. Many interjections, such as “Wow,” “No,” “Um,” “Well,” “Ouch” and “Hurray” are single words, but interjections can also be multi-word phrases such as “Oh well” and “My gosh.” Interjections can occur at the beginning of a sentence, as in “Excuse me, is someone sitting here?” or at the end of a sentence, as in “It’s snowing again, huh?”
Other examples of interjections and the feelings they convey include “Oops,” which conveys that someone has done or said something by accident; “Ew,” which conveys disgust; “Yahoo,” which conveys exhilaration; and “Whoa,” which expresses awe and surprise.
When the name of a person being addressed is unrelated to the rest of the sentence, as in “John, go to bed,” the name is considered an interjection.