unable◼◼◼(not able) adjective [UK: ʌn.ˈeɪb.l̩] [US: ʌ.ˈneɪb.l̩]He is unable to do it. = Il est incapable de le faire.
incapable◼◼◼(not being capable) adjective [UK: ɪnˈk.eɪ.pəb.l̩] [US: ˌɪnˈk.eɪ.pəb.l̩]He is incapable of telling a lie. = Il est incapable de mentir.
unfit◼◼◻(not fit; not having the correct requirements) adjective [UK: ˌʌn.ˈfɪt] [US: ən.ˈfɪt]
feckless◼◻◻(without skill, ineffective) adjective [UK: ˈfe.klɪs] [US: ˈfe.kləs]The Democratic Party appears both feckless and sclerotic. = Le Parti démocrate paraît à la fois incapable et sclérosé.