Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
kneel [niːl] (pt, pp knelt) vi (also: kneel down)(action) встава́ть*(встать*perf) на коле́ни (state) стоя́ть (impf) на коле́нях
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.