31a For instance, caviar's fine quality (8) DELICACY Why?
7d Fill up again? With beer it could be reprehensible (9) REPLENISH Why?
22d Very timid, almost vertical shot at Wimbledon? (6) VOLLEY Why?
31a: double definition:- for instance, caviar / fine quality 22d: very = V, timid almost vertical = yello(w) reversed = ELLOY [vertical means reversed for a down clue]