The trial court properly permitted the seven-year-old complainant to testify under oath. The voir dire established that she understood the nature and consequences of an oath (CPL 60.20), since she knew the difference between the truth and a lie, and that the word "swear" means "that you will always tell the truth" (see, People v. Parks, 41 N.Y.2d 36, 50). That a child states she would lie to protect her mother from being hurt does not, standing alone, require a contrary finding.
Defendant failed to preserve for appellate review his claim that the expert witness' testimony went beyond explaining behavior not within the jury's understanding (CPL 470.05), and we decline to review in the interest of justice. In any event, the claim is meritless since the testimony was offered to establish unusual behavior manifestations in some sexually abused children, and not to prove that complainant exhibited any of the manifestations (see, People v. Taylor, 75 N.Y.2d 277).
Concur — Sullivan, J.P., Carro, Wallach, Rubin and Williams, JJ.