The Simple Present
To form the simple present verb in the 3rd person singular you usually add only an ~s to the end of the verb.
drink-drinks run-runs see-sees snow-snows
dream-dreams rub-rubs sleep-sleeps write-writes
There are, however, many exceptions to the normal spell rule for forming the 3rd person singular verb.
If a verb ends in the letters ~sh, ~ch, ~ss, or ~x the 3rd person singular verb is formed by adding ~es to the end of the verb.
push-pushes teach-teaches kiss-kisses fix-fixes
If the verb ends with a consonant + ~y, change the ~y to ~i and add ~es to form the 3rd person singular verb.
If the verb ends in a vowel + ~y, add ~s to the verb to form the 3rd person singular verb.
The verbs have, go, and do are irregular verbs.
have-has go-goes do-does