A shared feature of the Germanic languages is the occurrence of complex verbs consisting of the verb itself and what I refer to as the adverbal unit (AU). I examine the nature of the units that can be inserted into such complex verbs and compare intercalation patterns in AU-Vs and V-AUs. AU-Vs are found to be much more resistant to intercalation than V-AUs. The former accommodate the past participle marker, the infinitival linker, and—less commonly—verbs, whereas the latter accommodate NPs, ADVPs, and—less commonly—both phrase types concurrently. Thus, V-AUs may be split by more syntactic as well as heavier material than AU-Vs. I argue that this difference in cohesiveness is due to varying degrees of coactivation of Vs and AUs. The constituents of AU-Vs show a higher degree of coactivation than those of V-AUs. Adverbal units depend for their activation on the prior activation of verbs more than verbs depend for their activation on the prior activation of adverbal units. These different activation patterns lead to different degrees of cohesiveness and hence to different intercalation possibilities in the two verb types. Although intercalation is compulsory in some contexts, it proves to be a dispreferred option.*