"Swan Lake," with its demanding principal, soloist and corps roles, is difficult enough for a ballet company new to the 19th-century classics to dance convincingly. The ballet also requires superior acting and mime skills to succeed as theater, and both received short shrift last night at the Kennedy Center Opera House when Ballet West presented the second performance of its handsomely mounted production of the Tchaikovsky ballet.

As Odette, Lee Provancha Day was overly fearful of Prince Siegfried's advances and held back technically to make herself appear weak. As Odile, she proved a surprisingly strong technician, dancing her solo cleanly, and fearlessly tackling the famous fouette's. Unfortunately, she portrayed Odile as a bad woman in a turn-of-the-century melodrama, a hootchy-kootchy danced at full gallop in the coda of the grand pas de deux being but one example of her overdone portrayal of a seductress.

By the fourth act, she had pulled both parts of her character's personality together; her Odette's languor turned to warmth, her Odile's superficial sexiness changed to urgent passion. Technically, Day has all the equipment for the Swan Queen. With coaching in subtlety, she could be excellent in the role.

As Siegfried, Bruce Caldwell was a sympathetic partner and a much stronger technician than his performance in "Etudes" earlier in the week had foretold. He, too, however, acted amateurishly at times.

This production rushes the mime that it doesn't ignore. In the first act, for example, much attention is paid to the irrelevant question of Siegfried's drinking habits while the crucial passage where the Queen Mother explains how, when and why he must marry is reduced to a single jab at the ring finger. Joseph Clark, as the Jester, and Mark Borchelt as the evil Von Rothbart, were the only members of the company who looked comfortable in mime.

The dancing throughout the evening was at an encouragingly high level.