Hesitant
Part of speech: adjective
Definition: Tending to hesitate, wait, or proceed with caution or reservation.
Example sentence: I'm a bit hesitant to do anything because I'm actually kind of lazy and I'd like an easier life from now on. The world's a massive place with lots of early mornings and late starts when you're working.
Uncertain
Part of speech: adjective
Definition: not known for certain; questionablenot yet determined; undecidedvariable and subject to changefitful or unsteadyunpredictable or capricious
Example sentence: If isolation tempers the strong, it is the stumbling-block of the uncertain.