In English, H occurs as a single-letter grapheme (with value /h/ or silent) and in various digraphs, such as ch (/tʃ/, /ʃ/, /k/, or /x/), gh (silent, /ɡ/, or /f/) , ph (/f/), rh (/r/), sh (/ʃ/), th (/θ/ or /ð/), wh (/w/, /hw/).H is silent in a syllable rime, as in ah, ohm, dahlia, cheetah, pooh-poohed. H is often silent in the weak form of some function words beginning with H, including had, has, have, he, her, him, his; and in some words of Romance origin and, for some speakers, also in an initial unstressed syllable, as in “an historic occasion”, “an hotel”.
In the German language, the name of the letter is pronounced /haː/. Following a vowel, it often silently indicates that the vowel is long: In the word erhöhen “heighten”, only the first <h> represents /h/. In 1901, a spelling reform eliminated the silent <h> in nearly all instances of <th> in native German words such as thun “to do” or Thür “door”. It has been left unchanged in words derived from Greek, such as Theater “theater” and Thron “throne”, which continue to be spelled with <th> even after the last German spelling reform.