apprehensive, discerning -- (quick to understand; "a kind and apprehensive friend"- Nathaniel Hawthorne)
apprehensive, worried -- (mentally upset over possible misfortune or danger etc; "apprehensive about her job"; "not used to a city and worried about small things"; "felt apprehensive about the consequences")
apprehensive -- (in fear or dread of possible evil or harm; "apprehensive for one's life"; "apprehensive of danger")
(Sound)
