An interjection is a word added to a sentence to convey emotion. It is not grammatically related to any other part of the sentence.
You usually follow an interjection with an exclamation mark (!). Interjections are uncommon in formal academic prose, except in direct quotations.
The highlighted words in the following sentences are interjections:
Learn about interjections thru these videos:
After watching the previous videos, try these other links so as to study and practice about injections.
Study section
Practice