How do you change swamp into a suffix?

You can't directly change "swamp" into a suffix. Suffixes are added to the end of a word to modify its meaning, and "swamp" is a complete word on its own.

However, you can use parts of "swamp" to create a suffix:

* -swamp: This is a possible suffix, but it's not commonly used. You could use it to create words like "rain-swamp" (a place with excessive rain) or "snow-swamp" (a place with heavy snow).

* -y: This is a suffix that can be added to some words, including "swamp", to create an adjective. For example, "swampy" means "characterized by swamps."

Ultimately, whether a word can be used as a suffix depends on usage and acceptance by the English language. If you're looking for a way to describe something related to swamps, using "swampy" or creating a new word using "-swamp" are options, but be aware they might not be universally understood.