• Observe (someone's) behavior
• Observe (someone's) bowerbird
• Observe (someone's) capillaries with a capillaroscope
• Observe (someone's) vernation
• Observe (someone's) waggliness
• Observe (someone) closely
• Observe (someone) from a distance
• Observe (someone) lammergeier
• Observe (someone) sassaby
• Observe (someone)'s squirrelfish