Читать книгу The Grammar of English Grammars - Goold Brown - Страница 102

A diphthong is two vowels joined in one syllable; as, ea in beat, ou in sound. In oe or æ, old or foreign, the characters often unite.

A proper diphthong is a diphthong in which both the vowels are sounded; as, oi in voice, ow in vow.

An improper diphthong is a diphthong in which only one of the vowels is sounded; as, oa in loaf, eo in people.

A triphthong is three vowels joined in one syllable; as, eau in beau, iew in view, oeu in manoeuvre.

A proper triphthong is a triphthong in which all the vowels are sounded; as, uoy in buoy.

An improper triphthong is a triphthong in which only one or two of the vowels are sounded; as, eau in beauty, iou in anxious. The diphthongs in English are twenty-nine; embracing all but six of the thirty-five possible combinations of two vowels: aa, ae, ai, ao, au, aw, ay—ea, ee, ei, eo, eu, ew, ey—ia, ie, (ii,) io, (iu, iw, iy,)—oa, oe, oi, oo, ou, ow, oy—ua, ue, ui, uo, (uu, uw,) uy.

Ten of these diphthongs, being variously sounded, may be either proper or improper; to wit, ay—ie—oi, ou, ow—ua, ue, ui, uo, uy.

The proper diphthongs appear to be thirteen; ay—ia, ie, io—oi, ou, ow, oy—ua, ue, ui, uo, uy: of which combinations, only three, ia, io, and oy, are invariably of this class.

The improper diphthongs are twenty-six; aa, ae, ai, ao, au, aw, ay—ea, ee, ei, eo, eu, ew, ey—ie—oa, oe, oi, oo, ou, ow—ua, ue, ui, uo, uy.

The only proper triphthong in English is uoy, as in buoy, buoyant, buoyancy; unless uoi in quoit may be considered a parallel instance.

The improper triphthongs are sixteen; awe, aye—eau, eou, ewe, eye—ieu, iew, iou—oeu, owe—uai, uaw, uay, uea, uee.