Prepositions link the object of a sentence or clause to the noun or verb named before it.
A preposition defines the relationship between a noun or verb and an object . Prepositions normally appear before the object :

I gave the book to Joan.

-- Preposition "to" links object "Joan" to noun "book"

We were surprised by the storm.

-- Preposition "by" links object "storm" to verb "surprised"

Common prepositions include

above about across after
against along among around
at before behind below
beneath beside between beyond
by down during except
for from in inside
into like near of
off on since to
toward through under until
up upon with within

Usually, the object follows the preposition. A preposition appearing at the end of a sentence sometimes sounds awkward because we expect to find an object:

This is the present we bought the wrapping paper for.
We bought the wrapping paper for this present.

Another danger in placing the preposition at the end of a sentence lies in separating the preposition from the object with too many words:

She gave me the newspaper she had walked over two miles to the store for.
She gave me the newspaper for which she had walked over two miles to the store.

Chose the preposition appropriate for the verb and object:

accompanied by a person
accompanied with a thing
accused of a wrong
accused by a person
in accordance to a rule
in accordance with a person
agree to (or about an idea)
agree with a person
correspond to an object
correspond with a person
differ from a person or thing
differ with a person
part from a person
part with a thing

Be careful of suspended prepositions separated by conjunctions . The suspended preposition must be appropriate for each verb :

I am proud and pleased for you.

-- Preposition "for" is incorrect with "proud"

I am proud of and pleased for you.