How do you make words ending in ful into plural?

Words ending in "-ful" are treated as regular nouns when forming the plural. You simply add "-s" to the end of the word.

Here are some examples:

* Beautiful: Beautifuls

* Careful: Carefuls

* Helpful: Helpfuls

* Wonderful: Wonderfuls

* Successful: Successfuls

However, it's important to note that some words ending in "-ful" are not used in the plural form in everyday language. Instead, you might use a different phrase or use the singular form with a modifier.

For example, instead of saying "They were all beautifuls," you might say "They were all beautiful women" or "They were all very beautiful."