Ülesanne 3.

G = { S->aSBC aB->ab bB->bb cB->BC CC->C }
S->aBC bC->bc CB->BC cC->cc

Paar näidet, mis peaksid kinnitama, et grammatikat G saab kasutada keelde L kuuluvate sõnade tekitamiseks.
 
S => aBC => aBCC => abCC => abcC => abcc
S => aSBC => aaSBCBC => aaSBBCC => aaaSBCBBCC => aaaaBCBCBBCC =>
  => aaaabCBCBBCC => aaaabCBCBBC => aaaabBCCBBC => aaaabBCBBC => aaaabBBCBC =>
  => aaaabbBCBC => aaaabbbCBC => aaaabbbcBC => aaaaabbbBCC => aaaabbbbCC =>
  => aaaabbbbC => aaaabbbbc