A discussion about using 'while' versus 'whilst' and 'burned' versus 'burnt'.
In American English whilst is not normally used. In British English while and whilst are more or less interchangeable when the meaning is although or whereas.
Whilst many people agree that boxing is dangerous, little has been done so far to ban it.It will remain cold in the west, eastern areas should be noticeably milder.
In the meaning of when, whilst is significantly more formal and may appear archaic. Compare:
I first met her while I was working for a company in the Midlands.I first met her whilst working for a company in the Midlands.
Similarly amongst and amidst are more formal and literary than among and amid, although in one or two phrases, for example amongst others, they may occur quite frequently. Incidentally, one American source dismisses these as “Briticisms or archaisms”.
The verbs burn, dream, lean, learn, smell, spill and spoil are all regular in American English and are written as burned, dreamed, leaned etc.
In British English they can be regular but irregular past tenses and participles with –t tend to be more common (burnt, dreamt, leant etc).
If you would like to make a generalised distinction in British English, it could be argued that the –t form of the past participle is more likely to be found in prenominal adjectival position than the –ed form. For example:
I don’t like burnt toast.
I don’t like burned toast.
The latter seems odd in British English. Arguably, the –ed form is more common as the past simple form of the verb, as in:
He burned all his old photos.