she carefully carried the glass jar
Carefully, pal, that's a rattlesnake!
With caution.
The word "on" is the preposition in this sentence.
You must tread carefully here & obey the site's rules.
Jonah said "I carefully put the glass on the bed."
The word carefully is already an adverb.An example sentence for you is: "She carefully unwrapped the chocolate, hoping for a golden ticket".
He executes his duties carefully.
carefully or cautiously
Let me arrange this example carefully.
the carpenter measures the wood carefully.
read that sentence carefully and tell me if that is one word