In Slavic languages, iotified vowels are preceded by a palatal approximant before a vowel, at the beginning of a word, or between two vowels in the middle of a word, creating a diphthongoid, a partial diphthong. In the Greek alphabet, the consonant is represented by iota (ι). For example, the English "apple" is cognate to Russian "яблоко (jabloko)": both come from Proto-Indo-European stem *ābol-. As a result of the phenomenon, no native Slavic root starts with an or an but only with a and ; although other vowels are possible.