Many Spanish verbs necessarily need to be complemented by a preposition, such as: “Advertir de”, “Carecer de”, among others.
Prepositions are usually found at the beginning of the syntactic constituent to which they modify. By linking words, prepositions function as invariable parts of the sentences that are responsible for denoting the link of the terms to each other.
It is important to keep in mind that the different prepositions can come to indicate a great variety of elements. Thus, for example, they can be used to indicate a place, an origin, a motive, a means or even a destination, among many other things.
To understand this, just use the preposition “a“. Thus, when used in the phrase “Voy a la biblioteca”, it comes to indicate an address, while if it is used in sentences such as “Estamos a 5 de mayo de 2019” it makes clear one day.
The preposition are 23:
a
ante
bajo
cabe
con
contra
de
desde
en
entre
Asia
hasta
para
por
según
sin
sobre
tras
durante
mediante
versus
día