· This list focuses on adding /shun/ to base words. Specifically, how a word changes its spelling when adding -sion, -tion and -ission. In words that end in -d or -de, the -de is dropped and -sion is added. For words that end in -be, the -be is changed to a p and -tion is added. Words that end in -it, the -it is dropped and -ission is added. There are three categories for this sort.