The first chapter gives a definition of so called verbs of incomplete meaning and suggests two criteria for their distinction from lexical verbs. Firstly, one must distinguish between the usage of infinitives as verbal additions to verbs of incomplete meaning within a complex predicate and the usage of infinitives as valency complements to lexical verbs. So for instance in the sentence Boji se priznati što se dogodilo ((He) is afraid to admit what happened) the infinitive phrase and the implicit subject are valency complements to the verb boji se (to be afraid of) since they are specific in the sense that all other complements apart from the subject denoting a human agent and the objective genitive denoting the cause of emotion are ruled out. As opposed to this, in the sentence Mora priznati što se dogodilo ((He) has to/must admit what happened) the infinitive is not a valency complement to the modal verb since this verb is not selective towards its complements (apart from their necessary infinitive form): theoretically every modal verb can be combined with every lexical verb in the infinitive form. The second chapter explains the basic syntax of modal verbs as a subgroup of verbs of incomplete meaning. Firstly, chapter 2.1. gives a definition and a classification of modal verbs in the Croatian language. In chapter 2.2. on the syntax of modal verbs in the Croatian language we discuss among other things the use of modal verbs with or without the infinitive form, parts of sentence claimed to be introduced by the modal verb itself, the syntax of the Croatian verbs željeti (wish) and htjeti (want) which differ in certain aspects from other modal verbs, the structure da + infinitive as an alternative to the infinitive form used with the modal verb and finally the status of sentences in which both modal and lexical verbs are used (simple or complex sentence). Chapter 2.3. gives a contrastive overview of certain syntactic aspects of modal verbs in the German language. The theoretical background for the analysis is provided by the dependence grammar and the valency theory combined with a synchronic, descriptive and contrastive approach.