1. Suffixes: These are letters added to the end of a word. They can dramatically change the word's function:
* -ing (verb to gerund/noun): "Singing" can be a verb ("He is singing") or a noun ("Singing is her passion").
* -er (verb to noun): "Teach" (verb) becomes "teacher" (noun).
* -ly (adjective to adverb): "Happy" (adjective) becomes "happily" (adverb).
* -ment (verb to noun): "Develop" (verb) becomes "development" (noun).
2. Prefixes: These are letters added to the beginning of a word. They often change the meaning but not necessarily the part of speech:
* un- (opposite): "Happy" becomes "unhappy" (both are adjectives).
* re- (again): "Do" becomes "redo" (both are verbs).
3. Context: The surrounding words in a sentence can determine the part of speech:
* "Run" can be a verb ("He runs fast") or a noun ("He went for a run").
* "Back" can be an adverb ("Come back") or a noun ("He hurt his back").
4. Internal Changes: Some words change form internally to become a different part of speech:
* "Good" (adjective) becomes "better" (adjective) and "best" (adjective).
* "Strong" (adjective) becomes "strength" (noun).
5. Specialized Uses: Some words have specific uses that can change their part of speech:
* "Up" can be an adverb, preposition, or noun, depending on its function in the sentence.
It's important to remember that parts of speech can be flexible and understanding context is key to identifying them accurately.