Possible Clues:

• ''What ___ thinking?''
• 'What ___ thinking?'
• "How __ to know?"
• "Now where ___?"
• "OK, now where ___?"
• "Now then, where ___?"
• 'Where ___?'
• ''What --- thinking?''
• 'Now, where ___?'
• 'What -- to do?'