What is a prefix of suffix for the word gratitude?

"Gratitude" doesn't have a prefix or suffix. It's a standalone word.

Here's why:

* Prefixes are word parts that are added to the *beginning* of a word to change its meaning.

* Suffixes are word parts that are added to the *end* of a word to change its meaning.

"Gratitude" is a complete word with its own meaning. It doesn't have any parts added to the beginning or end to create its meaning.