Programming languages for Software-Defined Networks (SDNs) provide higher abstractions on top of hardware-based APIs like OpenFlow. Researchers started to develop SDN programming languages based on mathematical foundations, which makes these languages amenable to verification and allows network administrators to answer questions about correctness of their policies, reachability within the network and performance of the network. However, these languages are only able to capture a limited set of properties and lack support for fully automated verification. In this paper we first highlight different issues of existing programming languages enabling network verification for SDNs and describe ongoing research on a new SDN language that tackles the aforementioned issues.