Vowel whose quality does not change over the duration of the vowel is called a monophthong. Monophthongs are sometimes called "pure" or "stable" vowels. A vowel sound that glides from one quality to another is called a diphthong, and a vowel sound that glides successively through three qualities is a triphthong. All languages have monophthongs and many languages have diphthongs, but triphthongs or vowel sounds with even more target qualities are relatively rare cross-linguistically. English has all three types: the vowel sound in "hit" is a monophthong , the vowel sound in "boy" is in most dialects a diphthong , and
Types of marriages Types of marriages The type, functions, and characteristics of marriage vary from culture to culture, and can change over time. In general there are two types: civil marriage and religious marriage, and typically marriages employ a combination of both (religious marriages must often be licensed and recognized by the state, and conversely civil marriages, while not sanctioned under religious law, are nevertheless respected). Marriages between people of differing religions are called interfaith marriages, while marital conversion, a more controversial concept than interfaith marriage, refers to the religious conversion of one partner to the other's religion for sake of satisfying a