prepositions and adverb particles

I stand on the table. on---is a preposition
you cannot say (I stand the table on)
I put off the fire. off---is an adverbial particle.
You can say (I put the fire off)
I look at the sky. at---is a preposition.
you cannot say (I look the sky at)
I look up the word in the dictionary. up---is an adverbial particle.
You can say (I look the word up in the dictionary)
I hope that the above can help you.