sentences:  In some other words, the diphthong becomes a two-syllable form with a semivocalic /j/ in between.With some exceptions, native Turkish words follow a system of vowel harmony, meaning that they incorporate either exclusively back vowels () or exclusively front vowels (), as, for example, in the words "karanlıktaydılar" ('they were in the dark') and "düşünceliliklerinden" ('due to their thoughtfulness').only occur in the initial syllable.