Richard Traynor appeals from his convictions of unlawful sexual contact, 17-A M.R.S.A. § 255(l)(c) (1983 & Supp. 1988), and assault, 17-A M.R.S.A. § 207 (1983 & Supp. 1988), after a jury trial in the Superi- or Court (Cumberland County; Brodrick, J.). We affirm the judgments.

We find no clear error in the Superior Court’s determination that the child prose-cutrices were competent to testify. Both children demonstrated an ability to express themselves “so as to be understood by the judge and jury,” and a sufficient understanding of the duty to tell the truth. State v. Hussey, 521 A.2d 278, 280 (Me. 1987).

We also find no abuse of discretion in the Superior Court’s rulings on discovery violations. State v. Landry, 459 A.2d 175, 177 (Me. 1983). Because the defendant waived at oral argument the final issue regarding the sufficiency of the evidence, we do not address it here.

The entry is: Judgments affirmed.

All concurring.