Related Clues:

• It's not optional
• Be without
• Be out of
• Will accept nothing less than
• More than just ask
• Do as requested
• Triage factor
• Essential thing
• If __ be
• Supply's partner
• Insist
• Require as a result
• Price factor
• Bind legally
• ''Mr. Watson ... I ___ you!'' (A.G. Bell)