To give life, action, or motion to; to make vigorous or active; to excite; to quicken; as, fresh fuel enlivens a fire
To give spirit or vivacity to; to make sprightly, gay, or cheerful; to animate; as, mirth and good humor enliven a company; enlivening strains of music
To enliven events, situations, or people means to make them more lively or cheerful. Even the most boring meeting was enlivened by Dan's presence. to make something more interesting