Here's a breakdown:
* Adding a suffix starting with a consonant: You typically don't need to change the base word's spelling.
* Example: "care" + "ful" = "careful"
Exceptions:
* Words ending in "y" preceded by a consonant: Change the "y" to "i" before adding the suffix.
* Example: "happy" + "ness" = "happiness"
* Words ending in a silent "e": Drop the "e" before adding the suffix.
* Example: "hope" + "ful" = "hopeful"
* Words ending in "c" followed by a consonant: Change the "c" to "k" before adding the suffix.
* Example: "picnic" + "ing" = "picnicking"
* Words ending in "ge" or "ce": Sometimes, the "e" is retained, but this is more of a matter of pronunciation than a hard rule.
* Example: "courage" + "ous" = "courageous"
Let me know if you'd like specific examples or have any other questions!