Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
INDIRECT OBJECT
The indirect object is the first of two contiguous nouns, pronouns, or other nominals in a predicate that contains a transitive verb and where each of the nouns has a different referent: in the sentence Jack gave Jill the book, book is the direct object, and Jill is the indirect object, the receiver of the thing on which the transitive verb acted. (Some grammars say that a to is “understood” before the first noun, as in Jack gave [to] Jill the book, but the explanation seems as strained as the example.) The syntax of these sentences is always the same—indirect object first, direct object second—unless the sentence uses a periphrastic construction with the preposition to, as in Jack gave the book to Jill, or unless the verb is one of the handful that permit an object complement.
