  We present a system composed of two flux qubits and a transmission-line
resonator. Instead of using the rotating wave approximation (RWA), we analyse
the system by the adiabatical approximation methods under two opposite extreme
conditions. Basic properties of the system are calculated and compared under
these two different conditions. Energy-level spectrum of the system in the
adiabatical displaced oscillator basis is shown, and the theoretical result is
compared with the numerical solution.
