Why are there five different sentence patterns?

       There two types of verbs in English; one is Intransitive

        Verb 不及物動詞) and the other is Transitive Verb.

        (及物動詞).

       An intransitive verb does not have an object. It is often

       followed by nothing or a subject complement which can be

       an adjective or a noun.  

       For example:

       S + Vi                 John ran.

       S + Vi + SC     John looks cool. (cool- adjective)      

                                 John is a doctor. (doctor- noun)

      When a transitive verb is used, the sentence can appear

      as the patterns below

      S + Vt+ O                 John likes sports.

      S + Vt + IO + DO     John asked the teacher 

                                          a question.     

      S + Vt + O + OC       John calls his girlfriend "Sweaty". 

      Note: Some verbs can function transitively and intransitively

      with different meanings.