Stuck on the last 6 of yesterday's crossword (this is more than I've ever managed to do before!). Would be most grateful for help:
6d Hold out a model of repair (4) ?a?t 15d Result of operation - contention (10) d?f??????? 21a In English school fundamentals, not one mistake (5) Could be 'error' but don't understand English school bit 26d City offering choice of ends of Holy week (4) 28a Empty net (5) 25a TIme divers used to dip into northern river (7) T?????? (I keep thinking Humber, but thumber means nothing to me).