Which words use a prefix or suffix? scientists planet view used from all impossible thought telescopes over Stargazers find

A prefix is a group of letters placed before the root of a word. For example, the word “unhappy” consists of the prefix “un-” [which means “not”] combined with the root (or stem) word “happy”; the word “unhappy” means “not happy.” A suffix is a group of letters placed after the root of a word.

Explanation:

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