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An interjection has no real value in grammar, they are usually spoken, less often written. Words such as 'Oh', 'Ah', 'Hey', 'Hi', 'Hmmm', 'Eh?' are all interjections
In Grammar

What is an interjection?

Interjections demonstrate emotion and are usually separated from  the rest of the sentence by an exclamation point, and sometimes by  a comma if the emotion is less stressed… Continue reading

In Grammar

Interjections are or and but?

Please ask your question in a COMPLETE sentence so that people will be able to understand what you are asking. And no, or and but are not interjections. Interjections are word… Continue reading

In Grammar

Is neither a interjection?

An interjection is an exclamatory word like Hey! or Whoops! or Yipes!   'Neither' can be a conjunction, an adjective or a pronoun. See related link.

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Is an interjection an emotion?

  No, an interjection is used to express an irrepressible emotion by "interjecting" words like Hey! or Ouch! or Holy Cats! into a sentence without affecting its grammar.

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In Grammar

What is interjection noun?

  Interjection nouns are words that express strong feelings.   example: wow, Ouch, Oh

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