sentence: Two people are demonstrating Tai Chi. sentence:  There is a garden with colorful flowers shown outside the Tai Chi school building. sentence:  The instructors wearing blue robes are showing the basic moves used in Tai Chi. sentence:  They are swaying their hands above their heads from left to right. sentence:  Then the instructor demonstrates arm strength by tapping his right arm over his extended left arm. sentence:  Both the instructors stand facing each other as they demonstrate slow and gradual hand movements.