He was supposed to be there at seven, but he was running behind.
In the hurry to evacuate, his laptop was left behind.
Preposition
It's a preposition.
Adverb
Like this: I did my history homework yesterday. That's how you use yesterday as an adverb in a sentence
Adverb
He fell behind during the hike.
(You would have to use the adverb, which is tenderly.) She touched his face tenderly.
In the English language, "fire" has no adverb form.
Profoundly is a adverb.
She jumped high up into the air. The word "high" is an adverb in the sentence above.
the adverb for easily is still easily but it depends on how it is being use in a sentence.
Correctly is the adverb in that sentence.