I really want to know as at what point the letter "H" is silent or pronounced at the begining of a particular word.i'll be very happy if i can be free from this longtime shackles of confusion.
Usage here is complicated and varies, especially between American and British English (where <h> dropping is very common in some dialects), but maybe the following will help:
The letter <h> is pronounced [h] only at the beginning of syllables and before a vowel sound: hat, ahead, prohibit, etc.
It is never pronounced in syllable final position, as in ah, oh, Messiah
. It is also never pronounced as [h] in the consonant digraphs <ch>, <th>, <ph>, <sh>, and <rh>. It is usually not pronounced in the digraph <wh>, though some people do pronounce a soft [h]-like sound before the [w], as in [h
wAl] for <whale>, though most people do not pronounce the [h
]: [wAl]. Also in a few words the digraph <wh> is pronounced [h]: who, whole, wholly, whom, whoop, whore, whose
. In the Irish surname Callaghan
<gh> is pronounced [h].
The letter <h> is often not pronounced between a stressed syllable and a following unstressed one: annihilate, graham, nihilism, shepherd, vehicle. It is also usually not prounced after the prefix ex-, even when the following syllable is stressed: exhaust, exhibit, exhilarate, exhort, exhume.
In a very few French adoptions initial <h> is not pronounced: hautboy, heir, honest, honor, hour and herb, usually.
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