The lesson of the past two American Ballet Theatre programs at the Kennedy Center Opera House, last night and Thursday, was that the dancer makes the dance. A truism, yes, but one that says something fundamental about the nature of theatrical dancing. Choreography is only a prescription, most of it consisting of blanks that need to be filled in. And the ways in which individual dance artists do the filling-in -- i.e., the dancing -- can alter the character of a ballet oftentimes radically.

Of the seven ballets seen in the course of the two evenings, two -- Paul Taylor's "Airs" and Jerome Robbins' "Other Dances" -- were receiving their first performances of the ABT season; the novelty in the others consisted of new castings.

"Airs" is a special case. Taylor is a "modern dance" choreographer; transferring a work created on his own company (even though the work had been planned originally for ABT) to a classical ballet troupe entailed an inevitable sea change. Ballet training, with its emphasis on verticality and on defying gravitational pull, runs counter to the Taylor idiom, in which roundedness, lightning shifts in dynamics and a sort of spongy bulkiness are axiomatic. What's amazing is that "Airs," unlike much other transplanted modern dance, not only survives the wrench, but does so without damaging loss. Maybe that's because Taylor's choreography for "Airs," responding to the noble serenity of its Handel score, is full of balleticisms. In any case, Thursday's cast, and most notably Kristine Soleri, Lise Houlton and Brian Adams, made the fusion seem eminently successful.

"Other Dances" couldn't be called unrecognizable, but the effect of its cross-grained casting last night -- Cynthia Gregory and Alexander Godunov -- was surely drastic. Gregory compensated for her outsize presence in this delicately featured piece with a nice gestural refinement; Godunov just looked clunky. The cast changes elsewhere, though, proved beneficial. Cheryl Yeager brought to Thursday's "Les Sylphides" an elfin musicality and charm that were wholly absent from the preceding night's account. Leslie Browne, Johan Renvall, Lise de Ribere and Ronald Perry gave the outer movements of "Bouree Fantasque" a lilting effervescence that had eluded the first performance. Similarly, Chrisa Kerimdas and Amy Rose put the life back in "Concerto" last night. And Robert La Fosse managed an arrestingly complex, sympathetic portrayal in "Billy the Kid," in his first try at the title role. Finally, Susan Jaffe infused last night's "Jardin Anime" with the same allure and brilliance that have marked her performances since the week's start.