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 rural communities Types of rural communities Sociologists have identified a number of different types of rural communities, which have arisen as a result of changing economic trends within rural regions of industrial nations. The basic trend seems to be one in which communities are required to become entrepreneurial. Those that lack the sort of characteristics mentioned below, are forced to either seek out their niche or accept eventual economic defeat. These towns focus on marketing and public relations whilst bidding for business and government operations, such as factories or off-site data processing. For instance, International Falls, Minnesota markets itself as a site