Possible Clues:

• Wish I could help by coming up with old forensic evidence on fleece
• It's impossible, returning racket with ball
• Up-and-coming politician leading a new party? Impossible
• ''Uh-uh''
• Local won't work with Bob over tin office
• 'Sorry, that's impossible'
• Admission of failure in retrograde study a don demolished
• Take up study with love? I won't oblige!
• Time-server coming up with old, off-putting response
• 'Impossible, my friend'