It about investigates how vowel duration and vowel quality affect degrees of vowel-to-vowel. The effects of these two factors on vowel-to-vowel articulation. it has Phonological duration differences due to vowel length. and it was hypothesized that shorter vowel duration could result in more vowel-to-vowel articulation. thus the susceptibility of different vowel quality to vowel-to-vowel articulation. this topic helps to know about vowel that has The pronunciation different.