Possible Clues:

• Though not dozy, almost give up Latin: so complex
• On the lookout for six pounds invested in big one
• Keeping careful watch
• Watchful, alert to possible danger
• Awake by 6.50, when imprisoned by soldiers
• Unofficial law-enforcer is never endingly watchful
• Attentive woman with enormous figure about 50
• Watchful living at resort
• Alert Roman poet sacrificing right over a set of books
• Wary learner gets stuck into jumbo after six