41. In the examples below, represents, =, and is spelled before back vowels and before front vowels. 42. Similarly before the back vowels , the velar continuant has the alternations and as shown in the examples below: 43. There was also a high back vowel , which is often interchangeable with and may have been an allophone. 44. In most languages, roundedness is a reinforcing feature of mid to high back vowels rather than a distinctive feature. 45. This merger does not occur where is realised as a back vowel , thus keeping the words distinct as and. 46. In practice, what are analyzed phonemically as unrounded back vowels are typically near-back in their actual articulation. 47. Before back vowels they are, and before front vowels ( written " pa ch ka " ). 48. Excluding recent loanwords, Hungarian words have either only back vowels or front vowels due to these vowel harmony rules. 49. However, the horizontal letters a1 \ 1W1 do appear to have all represented mid to high back vowels ,. 50. And can this fricative sound have other realisations such as [ x ] after back vowels like [ a ]?