In the study, I learnt that interjections, one of the parts of speech in English are used casually in spoken English and it's not advised to use them in written English especially when you are trying to be formal.
Here are the 8 parts of speech in English;
- Noun
- Pronoun
- Adjective
- Verb
- Adverb
- Preposition
- Conjunction
- Interjection