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Verbs ending with "s", "ch", "sh", "x" or "z"
When a verb ends with s, ch, sh, x or z, we add the letter e, and then we add the letter s.
In the following examples the part before the letter s is in purple and the letters es are in red.
miss => miss + es => misses kiss => kiss + es => kisses watch => watch + es => watches teach => teach + es => teaches wash => wash + es => washes push => push + es => pushes mix => mix + es => mixes fix => fix + es => fixes buzz => buzz + es => buzzes
In the following examples the part before the letter s is in purple and the letters es are in red.
| miss | => | miss + es | => | misses |
| kiss | => | kiss + es | => | kisses |
| watch | => | watch + es | => | watches |
| teach | => | teach + es | => | teaches |
| wash | => | wash + es | => | washes |
| push | => | push + es | => | pushes |
| mix | => | mix + es | => | mixes |
| fix | => | fix + es | => | fixes |
| buzz | => | buzz + es | => | buzzes |
Verbs ending with "o"
When a verb ends with o, we add the letter e, and then we add the letter s.
In the following examples the letter o is in purple and the letters es are in red.
go => go + es => goes do => do + es => does
In the following examples the letter o is in purple and the letters es are in red.
| go | => | go + es | => | goes |
| do | => | do + es | => | does |
Verbs ending with "y"
When a verb ends with y and there is a consonant before it, the y changes into ie. Then the letter s is added.
In the following examples the consonant is in blue, the part before the letter s is in green, and the letter s is in red.
fly => flie + s => flies try => trie + s => tries cry => crie + s => cries study => studie + s => studies
When a verb ends with y, and there is a vowel before it, we simply add the letter s to the verb.
In the following examples the vowel is in orange, the part before the letter sis in green, and the letter s is in red.
buy => buy + s => buys say => say + s => says pay => pay + s => pays play => play + s => plays enjoy => enjoy + s => enjoys
So these were the spelling rules for adding "s" in the Simple Present.Got it? Good! Let's practice it…
For spelling rules on other subject visit the Spelling Rules page.
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source: 
Spelling the - S Form
In the following examples the consonant is in blue, the part before the letter s is in green, and the letter s is in red.
| fly | => | flie + s | => | flies |
| try | => | trie + s | => | tries |
| cry | => | crie + s | => | cries |
| study | => | studie + s | => | studies |
When a verb ends with y, and there is a vowel before it, we simply add the letter s to the verb.
In the following examples the vowel is in orange, the part before the letter sis in green, and the letter s is in red.
| buy | => | buy + s | => | buys |
| say | => | say + s | => | says |
| pay | => | pay + s | => | pays |
| play | => | play + s | => | plays |
| enjoy | => | enjoy + s | => | enjoys |
So these were the spelling rules for adding "s" in the Simple Present.
Got it? Good! Let's practice it…
For spelling rules on other subject visit the Spelling Rules page.
.
source:
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Next activities 
Grammar Rules:
See our notes about the Simple Present Tense in English.
Pronunciation Rules:
You might be interested in the Pronunciation of -S at the end of words in English.
Grammar Rules: Pronunciation Rules: |
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