In 5G wireless communication systems, it is crucial to support efficient multiplexing of enhanced mobile broadband (eMBB) and ultra-reliable and low latency (URLLC) services in the same carrier, and maximize system capacity for both services. In this paper, we mainly discuss the scenario of multiplexing of eMBB and URLLC in a new radio (NR) downlink carrier. A new reference signal is designed in which a flag signal is also used as a reference signal for the scenario of dynamically sharing the resource between eMBB and URLLC. Simulation results demonstrate that the proposed method achieves significantly improved performance comparing previous methods.