What is an example of a suffix?

A suffix is a letter or a group of letters added to the end of a word that alters its meaning or grammatical function. "Happi-ness" illustrates this concept perfectly because the suffix "-ness" is added to the base word "happy." This transforms the adjective "happy" into a noun, referring to the state of being happy.

The other options exemplify prefixes or root words rather than suffixes. For instance, "pre-" in "pre-heat" and "un-" in "un-finish" are both prefixes that modify the meaning of the root words, indicating actions or conditions in relation to something else. Similarly, "re-" in "re-play" is another prefix indicating that an action is being repeated. Therefore, "happi-ness" stands out as the only option that correctly represents a suffix.