The paper deals with representation of obligatory participants of a situation described by the verb which do not get a syntactic role in the syntactic structure of a Khmer sentence, i. e. incorporation in the verb semantic structure, excorporation into a lexical complex, deictic zero, zero anaphors. Special attention is paid to the role of lexical complex, which is a unique resource of the Khmer language, and its use for implicit and explicit representation of the participants of the situation described. An issue of a particular interest is participants’ representation as a component of a lexical complex, rather than a component of the sentence syntactic structure. Language data of Modern Khmer, Middle Khmer, and Old Khmer is used to show that this mode of representation has been used throughout the whole period of the evolution of Khmer beginning with the Old Khmer inscriptions. An attempt is made to reveal the functional character of the phenomenon discussed. It is maintained that this strategy is used for semantic derivation, for a more detailed conceptualization of the situation described, as well as for word polysemy elimination in the text. Examples are cited where lexical complexes with incorporated participants are used to make up for the inherent semantic emptiness of predicates of evaluation. In case of participants incorporated in deictic verbs, the deictic zero in Khmer may refer to participants other than “observer”. Specific features of zero anaphora in Khmer are also mentioned.