listen [ˈlɪs ə n]

– to give attention with the ear; attend closely for the purpose of hearing; give ear.
– to wait attentively for a sound.
– Archaic. to give ear to; hear.

before 950; Middle English lis ( t ) nen, Old English hlysnan;  cognate with Middle High German lüsenen, Swedish lyssna;  akin to list.

look [lʊk]

– to turn one’s eyes toward something or in some direction in order to see.
– to glance or gaze in a manner specified.
– to use one’s sight or vision in seeking, searching, examining, watching, etc.

before 900;  (v.) Middle English lōk ( i ) en, Old English lōcian;  cognate with Middle Dutch lœken,  akin to dialectal German lugen  to look out; (noun) Middle English loke  act of looking, glance, countenance, derivative of the v.