core arguments = required arguments

    external argument = subject
    internal argument can be:  direct object, indirect object, prep phrase
      (internal arguments = complements)

oblique arguments = optional arguments
(oblique arguments = adjuncts)
___________

Examples:

Mary gave John the letter yesterday.

core arguments:
  external:  Mary
  internal:  indirect object:  John
                direct object:    the letter

oblique argument:  yesterday.
_________

Susan put the soup in the bowl with a spoon.

core arguments:
   external:  Susan
   internal:  direct object:  the soup
                 prep phrase: locative:  in the bowl

oblique argument: with a spoon.

CJ