Оказывается, перкалдываение вилки из правой в левую и обратно является "американским стилем", а неменяемость вилки и ножа - "континентальным":
The fork is held in the right hand and is used for eating. The knife is used to cut or spread something onto a food item. To use the knife, the fork is switched to the left hand or is laid down; to continue eating, the fork is switched back to the right hand. But, if you prefer to use the "continental" style of dining, in which the knife and fork are never switched, that is acceptable, too.
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