Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
submerge [səbˈməːdʒ] vt погружа́ть (погрузи́ть*perf) (в во́ду)
vi (submarine, sea creature) погружа́ться (погрузи́ться*perf) (в во́ду)
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.