1. -ation: Forms nouns from verbs, often indicating a process or action. Examples: *creation, education, celebration*
2. -ition: Forms nouns from verbs, usually related to a state or condition. Examples: *decision, position, addition*
3. -sion: Forms nouns from verbs, often related to a process or result. Examples: *extension, invasion, explosion*
4. -tion: Forms nouns directly from verbs, often indicating a process or result. Examples: *action, reaction, attention*
5. -ition: Forms nouns related to a state or condition, often from Latin or Greek roots. Examples: *petition, condition, ambition*
6. -tion: Forms nouns related to an action or state of being, often from French or Latin roots. Examples: *nation, motion, emotion*
7. -tion: Forms nouns related to a process or action, often with a specific focus on the outcome. Examples: *donation, taxation, irrigation*
It's important to note that the distinction between these suffixes is subtle and sometimes overlapping. The best way to determine the correct spelling is to consult a dictionary.