 The poem contains a complicated use of assonance ( the repetition of vowel sounds ) , as evident in line 19 , " O why did ye not melt , and leave my sense " , where the pairs ye / leave and melt / sense share vowel sounds . A more disorganized use of assonance appears in line 31 , " A third time pass 'd they by , and , passing , turn 'd " , in which the pairs third / turn 'd , time / by , and pass 'd / passing share vowel sounds . The first line exemplifies the poem 's consistent iambic pentameter scansion : 
 The poem <a href='uninflect' title='1'><mark>contains</mark></a> a complicated use of assonance ( the repetition of vowel <a href='uninflect' title='2'><mark>sounds</mark></a> ) , as evident in line 19 , " O why did ye not melt , and leave my sense " , where the pairs ye / leave and melt / sense share vowel <a href='uninflect' title='3'><mark>sounds</mark></a> . A more disorganized use of assonance <a href='uninflect' title='4'><mark>appears</mark></a> in line 31 , " A third time pass 'd they by , and , passing , turn <a href='null_genetive' title='5'><mark>'d</mark></a>" , in which the pairs third / turn 'd , time / by , and pass 'd / passing share vowel <a href='uninflect' title='6'><mark>sounds</mark></a> . The first line <a href='uninflect' title='7'><mark>exemplifies</mark></a> the poem <a href='null_genetive' title='8'><mark>'s</mark></a>consistent iambic pentameter scansion : 
The poem contain a complicated use of assonance ( da repetition of vowel sound ) , as evident in line 19 , " O why did ye not melt , and leave my sense " , where the pairs ye / leave and melt / sense share vowel sound . A more disorganized use of assonance appear in line 31 , " A third time pass 'd they by , and , passin , turn  " , in which tdapairs third / turn 'd , time / by , and pass 'd / ppassinshare vowel sound . The first line exemplify thdaoem  consistent iambic pentameter scansion :