Heat neither enters nor leave a system then its temperature:

Explanation

If heat neither enters nor leaves a system, then its temperature may rise or may fall. This is because the temperature of a system is determined by the balance of heat entering and leaving the system, as well as the work done on the system. If there is no heat transfer, then the only way for the temperature of the system to change is if work is done on the system. For example, if a gas is compressed adiabatically (no heat transfer), then the temperature of the gas will rise. This is because the work done on the gas increases the internal energy of the gas, which is equivalent to an increase in temperature. Conversely, if a gas is expanded adiabatically, then the temperature of the gas will fall. This is because the work done on the gas decreases the internal energy of the gas, which is equivalent to a decrease in temperature.