Prepositional adverb

Many word forms which are prepositions are also adverbs. We call them prepositional adverbs. Most of them are adverbs of place. They are used to form PHRASAL VERBS (for example, take over, come on, etc).

Let's see a list of common prepositional adverbs in the table below.

about	around	beyond	near	past	under
above	before	by	on	round	up
across	behind	down	opposite	since	within
after	below	in	outside	through	without
along	between	inside	over	throughout

Prepositions are usually in front of a noun phrase, whereas prepositional adverbs usually stand alone, without a following noun phrase. Let's compare:
(1)
Preposition: Sam stayed in the house.
Adverb: Sam stayed in.

(2)
Preposition: The guests were standing around the room.
Adverb: The guests were standing around.

Note:
(1) Prepositional adverbs are always stressed. Prepositions are frequently unstressed.
(2) Prepositional adverbs are sometimes called "particles".

I hope this article helps. If you have any question, please leave a comment below.