1. A method of transmission using a sidelink data channel by a terminal in a wireless communication system, the method comprising:performing a plurality of transmissions on the sidelink data channel using a plurality of resources,
wherein the plurality of transmissions using the plurality of resources is performed so as to satisfy the condition that:
for each priority level among a plurality of priority levels for the plurality of transmissions:
for transmissions having equal or lower priority than the priority level, a sum of resources utilizations for the transmissions is constrained to be equal to or less than a threshold corresponding to the priority level,
wherein the threshold is related to a maximum limit on resource utilization for transmitting with the priority level on the sidelink data channel.