1. 一般在动词结尾直接加s

   e. g.   help --- helps         climb --- climbs

          talk --- talks          sing --- sings

          tell --- tells          swim --- swims

          run --- runs            enjoy --- enjoys

2. 以s, x, ch, sh, o结尾的动词加es;

   如果词尾已有e, 直接加s

   e. g.   teach --- teaches    guess --- guesses

           wash --- washes      watch --- watches

           go --- goes          do --- does

           close --- closes      dance --- dances

           love --- loves        like --- likes

3. 以辅音字母 + y结尾的动词, 变y为i后, 加es

   e. g.   study --- studies    try --- tries    

           fly --- flies