cryptic crossword
1a Drifting debris, note plenty before lunch (7)
8a Guarantee the beast is by the river (6)
9a Flat screen first given by bookie?(5)
20a Speaker finds young marsupial about to swallow rodent (6)
23a Leaders (6)
24a Learning about one European river (5)
25a Change sea movement the wrong way (4)
11d Pudding is a melon, cooked (8)
Many thanks to anyone who can help.