Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
prae-ŏlĕo, ēre, v. n., to emit or exhale an odor beforehand (post-Aug.): ut crocus, ita somnus prius quam prope adsit, longe praeolet, Front. Ep. ad M. Caes. 1, 4 Mai.
* prae-ŏlo, ĕre, v. impers., to perceive before: ut praeolat mihi quod tu velis, Plaut. Mil. 1, 1, 41; v. Ritschl ad h. l.