Writing Systems of the World 9, Exercise 2: debt and ghost

debt: etymological respelling. The English orthography article says a "b" was
added to debt (and an "s" to island) to suggest a Latin or Greek origin. The b
was never pronounced.

ghost: printing. The article says ghost was "gost" in Middle English until a
Flemish spelling pattern was unintentionally substituted by early printers,
who were multilingual.

Two different causes: one a deliberate scholarly choice, the other an
accident of printing practice.