You say ‘erb (using the silent French ‘h’), I say herb (the way it’s spelt). Here’s a good example of the difference between the American pronunciation (usually referred to as General American, or GA) and the Received Pronunciation (British English, RP) of foreign loan words — ie. words that have been adopted into standard English from other languages, many from centuries ago. Many will argue that RP has tended more to assimilate these words and pronounce them according to English spelling-pronunciation rules rather than to the way the original word sounds. So fillet (or filet), meaning a small boneless cut of meat (derived from the French word filet), is pronounced by the Brits as “FILL-uht”, in the way that its English spelling prescribes. Americans prefer to approximate the French accent with their more exotic rendering, “fi-LAY”. However, there are many exceptions to this rule, as illustrated in some of the examples below.
Especially when it comes to words of French derivation, the distinction between GA and RP is governed largely by stress, with the Americans sticking more faithfully to the French tendency to emphasize the last syllable of the word, whatever the spelling (as in fillet above). Hence baton, beret, ballet and debris are all voiced differently on opposite sides of the Atlantic, with RP placing emphasis on the first half of the word and GA on the second; attaché and fiancé follow suit, with the second and final syllables stressed respectively by the Brits and the Americans. (There are exceptions; see below.) Croissant is another curious example: Americans order a “kruh-SAHNT”, where Brits prefer a KWAH-song. But this is a great example of just how these rules of thumb don’t really hold up: whereas GA follows the French rule of emphasis here by stressing the second syllable, RP probably does a better job of imitating the French vibe by approximating both the vowel and consonant sounds of the original word (“kw” for “cr”, “ah” for “oi”, the silent “nt” following the nasal-sounding “o”). So at the end of the day, there’s really no hard-and-fast rule about whether GA or RP more closely follows the original pronunciation of the word in its native language, and indeed this seems to vary according to the original language in question. The wonderful blog Separated by a Common Language looks more specifically at Spanish loan words and how and why they’re pronounced in GA & RP, and there’s a discussion about how German words are handled on the Word Reference Forum.
Here are a few examples of RP and GA pronunciations, with the one I feel more closely approximates the original word bolded.
herb: RP: herb; GA: erb
croissant: RP: KWAH-song; GA: kruh-SAHNT
valet: RP: VAL-lett; GA: val-LAY
fillet: RP: FILL-ett; GA: fi-LAY
address (as noun in postal sense): RP: a-DRESS; GA: ADD-ress
cigarette: RP: si-guh-RET; GA: SI-guh-ret
Van Gogh: RP: either Van-GOKH (rhyming with the “loch” of the Lochness Monster) or Van-GOFF; GA: Van-GO
schedule: RP: SHED-yule; GA: SKED-yule (Greek “sch” words are generally pronounced with the hard ‘k’, eg. school)
Risotto: RP: ri-ZOT-toe; GA: ri-ZOH-toe
Pasta: RP: PAS-tuh (first syllable rhyming with “lass”); GA: “PAH-stuh”