'carefully' originates from Old English, specifically the word 'carful,' where 'car' meant 'care' and '-ful' meant 'full of.' 'Altered' originates from Latin, specifically the word 'alterare,' where 'alter' meant 'other.'

'careful' changed from Middle English word 'careful' and eventually became the modern English word 'careful.' 'Altered' transformed from the Old French word 'alterer' and eventually became the modern English word 'alter.'

Initially, 'careful' meant 'full of care or concern,' and this meaning has largely remained the same in modern usage. 'Altered' initially meant 'to make other or different,' and this meaning has largely remained the same in modern usage.