The word "in" can only be an adverb when it acts by itself to modify a verb, with no noun following it as an object.
Example: The man walked in.
(adverb - we don't know what he's walking into)
Otherwise, it is a preposition, and the phrase can modify either nouns or verbs.
Example:
The hole in the ceiling became larger.
(preposition - an adjective phrase, modifying hole)
He works in the bank.
(preposition - an adverb phrase, modifying works)
Adverb: I had a hat on. Preposition: I didn't have any money on me.
Adverb
No, it is not a preposition. Tall is an adjective and possibly an adverb.
A preposition will use an object (noun, pronoun, or an equivalent phrase). Example: Getting dirty is part of being a cowboy. (being a cowboy is a noun phrase, object of the preposition of) Where an adverb might also be used as a preposition, look for an object: a noun or pronoun or the equivalent which normally follows the preposition. If there is none, the word in that usage is an adverb. Example: We walked on. (adverb) We walked on the beach. (preposition)
It is never an adverb. It is always a preposition. The word "within" can be an adverb or a preposition, and the word "forthwith" (immediately) is an adverb.
It is never an adverb. It is always a preposition. The word "within" can be an adverb or a preposition, and the word "forthwith" (immediately) is an adverb.
preposition
In this adverb form of "with" meaning "accompanying," along is an adverb and with is a preposition.
Yes "throughout" is a preposition.Yes, it can be a preposition. But it can also be an adverb by itself.
No, it is not a preposition. It is an adverb.
The word below can be an adjective, adverb or preposition. It is an adverb in the sentence: "To see another example, look below."
No. It is not a preposition. Twice is an adverb.