... A. UN-, IM-, IN-, DIS-, AND NON- The prefixes un-, im-, in-, dis-, and non- can be added to the beginning of some words. These prefixes mean “not.” Look at this example: un- + healthy ... compounds). Figure 13 : Types of pollution 12 ENGLISH FOR ENVIRONMENTAL STUDIES B. -AL, -ABLE, AND -FUL The suffixes -al, -able, and -ful can be added to the end of some words. These ... by adding the suffixes -al, -able, and -ful to the following words. Spelling Note: Change y to i before -al and -ful. noun (add –al) adjective verb (add -able) adjective co ast...