Prefixes and suffixes are important components of English vocabulary that can significantly affect the meaning of words. A prefix is a letter or group of letters that are added to the beginning of a word to change its meaning, while a suffix is added to the end of a word to modify its meaning or form a new word altogether.

Some common prefixes include “un-“ which means not or the opposite of, “dis-“ which means not or opposite of, and “re-“ which means again or back. For example, adding the prefix “un-“ to the word “happy” changes its meaning to “unhappy”, which means not happy. Adding the prefix “re-“ to the word “do” changes its meaning to “redo”, which means to do again.

Some common suffixes include “-ness” which means the state of or condition of, “-ment” which means an action or process, and “-able” which means capable of. For example, adding the suffix “-ness” to the word “happy” changes its meaning to “happiness”, which means the state of being happy. Adding the suffix “-able” to the word “read” changes its meaning to “readable”, which means capable of being read.

Knowing common prefixes and suffixes can help you to understand the meaning of words more easily and to build your vocabulary. You can also use prefixes and suffixes to create new words or to modify existing ones.