The main part of the word is the root . One of the easiest of all spelling guidelines to remember is that the root remains the same when the prefix un, dis , or mis is added. This rule also applies to spelling the verb that pairs with the third person singular noun or pronoun. Nouns ending in f or fe are made plural by changing the f or fe to v and adding es . There are so many exceptions to this rule that you may want to learn to spell the words that end in o individually.
Most verbs take the suffix s in the third-person singular.
Verbs ending in s, z, x, sh , or ch take the suffix es to form the third-person singular. Verbs ending in o preceded by a vowel add only s to form the third-person singular. Verbs ending in y preceded by a consonant change the y to i , and add es to form the third-person singular. Some verbs ending in o preceded by a consonant add es to form the third-person singular. When a word ending in e is preceded by a consonant, the e dropped when a suffix beginning with a vowel follows.