>>>>An before a muted H as in An hourglass (the h is silent in hourglass)
>>>>A before historical because the h is not silent.
>>>>(Although you will see and hear it both ways and it is acceptable - and probably common which is what you asked - to always use "AN" before any word that begins with "H")
>>>>
>>>I agree. I'm checking my husband's manuscript (he is transalting his book in English) and when I saw "an historical" it stroke me as wrong. That's why I want a correct literary usage.
>>
>>"into English"
>>"it struck me" Stroke is the nound from strike :-)
>>
>>I can't tell which one you've plumped for but "I have an headache" would sound dumb.
>
>Thanks. I should have checked my message myself and catch all these errors.
>
>Thanks again.

было удовольствием

Also "an horrific accident", obviously "an honour" - maybe words that are derrived from the French.

Most importantly, though, the letter is pronounced "aitch" not "haitch"

e.g. "an aitch-class submarine", the British "En aitch ess" (NHS) = national health service