When Do Suffixes Change?

They change the meaning of the root word, but not the part of speech. Suffixes go at the end of words. They change the meaning of the root word, and quite often the part of speech, as well.

Is there a rule for suffixes?

Rule 1: For words ending in two consonants, just add the suffix to the root word. Rule 2: For words that end in a short vowel sound followed by a consonant, you need to double the last letter then add the suffix.

Does the spelling of a suffix ever change?

Usually when you add a suffix to a root word the spelling of both stays the same: e.g. care + ful = careful But there are several important groups of words where the spelling of the root word changes when you add a suffix.