Related Clues:

• Wary
• Mindful of
• 'I'm ___'
• Whistle, maybe
• At the ready
• When repeated, start of a cheer
• Far from sleepy
• Bright-eyed and bushy-tailed
• Advance warning
• Knows about
• Watching
• Not taken by
• "___ victory!"
• Quick on the uptake
• Attentive