I am not a native speaker, and I find it very interesting that night is written with gh. Why is it spelled this way?
When you see a GH spelling in English and it's silent or not pronounced like G, you're dealing
with Middle English. That's the language for which English spelling was developed.
Middle English had an /h/ phoneme, and it occurred
both pronounced [h] before vowels
(where /h/ occurs in Modern English: Ha he who huh hey /ha hi hu hə he/)
and pronounced [x] (rather like German CH or Russian Х or Hebrew ח) after vowels.
It was spelled GH in those cases, because it was pronounced [x], instead of [h].
Part of the change to from Middle to Modern English was that the postvocalic [x] allophone of /h/
either disappeared (as in night), or mutated to another fricative, like [f] in enough or trough.
Once these had disappeared (leaving only fossils in the spelling), the prevocalic allophones, having no other H-like sounds to contrast with, mutated into the current bevy of voiceless vocal onsets.
protected by user140086 Jun 2 '16 at 8:11
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