WordNet sense 1 (a Swiss patriot who lived in the early 14th century and who was renowned for his skill as an archer; according to legend an Austrian governor compelled him to shoot an apple from his son's head with his crossbow (which he did successfully without mishap)):

William Tell

WordNet sense 2 (inform positively and with certainty and confidence):

assure

WordNet sense 3 (express in words):

say, state

WordNet sense 4 (give evidence):

evidence

WordNet sense 5 (narrate or give a detailed account of):

narrate, recite, recount, recount

WordNet sense 6 (give instructions to or direct somebody to do something with authority):

enjoin, order

WordNet sense 7 (mark as different):

differentiate, distinguish, separate, secern, secernate, severalise, severalize, separate, tell apart