Once this concordance mechanism (i.e., the assignment of the starting and end points of the verb to the R-loci of arguments) has been put in place for a group of verbs, other verbs may also adopt this morphological mechanism and become consistent verbs. These verbs may share some, but not all, attributes of transmission verbs. For example, communication verbs, such as PHONE or FAX, refer to two human participants, such as the verbs of transmission, and also the act of communication. In some languages (e.g.B. ASL and ISL), these signs have become verbs of concordance. Similarly, verbs such as TELL, ASK, ANSWER, TELL-A-STORY and ASL SAY-NO-TO have become verbs of concordance. As LM-M points out, there are many characteristics on which verbs coincide. I see this as an indication that with the introduction of the formal mechanism in a language, the semantic basis of the category becomes more opaque and that the grammatical characteristics of the elements are more prominent. These observations on the emergence of an agreement can be made in the following way. It seems that the use of spatial positions is a strong feature of the visual modality. Management is used in a wide range of circumstances; it appears in the gesture of the non-signatories, the pre-language gesture of hearing children and the first gestures and signs of deaf children (Casey 2003b).
However, the use of a steering description to distinguish the first and the non-first is not as widespread as the existence of a spatial but non-personal chord in the ABSL shows this. Berk (2003) found a similar asymmetry in two children who acquired ASL with relatively late exposure – they produced a relatively accurate location agreement, but they made many mistakes with no one`s agreement. Similarly, the systematization of directional verbs in the NSL, intergenerational differences in the marking of first-person objects in DSL, and the assimilation of reference signs across directional verbs (which leads to the nativization of these “foreign” signs) indicate that people`s consent systems do not come out of the act.