A tenant rented a small store from the owner of a commercial building under a five-year lease. The tenant vacated the premises at the end of the first year and refused to make any further lease payments. The owner did not agree to the termination of the contract and he was only able to find a new tenant two years later. What are the rights (and liabilities) of the parties? Who is obligated to pay the rent while the building was vacant for two years?