One of the biggest obstacles I have experienced teaching Spanish is the majority of my students do not understand English grammar. Many students have problems with even the most basic principles such as defining nouns and pronouns. One concept almost none of my students have understood over the years is the difference between definite and indefinite articles.
This basically boils down to the difference between the and a/an in English.
Ex. Do you know the new student? (This question is referring to someone specific- THE new student. There is a new student and the questions is directly asking about that person who DEFINITELY exists.)
Ex. Do you know a new student? (This question is more vague. Is there actually a new student? It’s not certain. If there is a new student or many new students, this question is not asking about one in particular. It’s asking in general if you know anyone in that category.)
Definite articles in Spanish translate to the in English. In Spanish there are four different options:
el, la, los, las
We have masculine singular, feminine singular, masculine plural, and feminine plural.
el gato- the cat
la vaca- the cow
los gatos- the cats
las vacas- the cows
Indefinite articles in Spanish translate to a or an in English when referring to one thing (a singular noun) and some when referring to more than one thing (a plural noun):
un, una, unos, unas
Again, we have masculine singular, feminine singular, masculine plural, and feminine plural.
un gato- a cat
una vaca- a cow
unos gatos- some cats
unas vacas- some cows
This very basic and fundamental grammar concept sneaks itself into other more advanced concepts as students progress through levels 4 and 5. Understanding the difference between definite and indefinite articles ranks high on my list of must-know Spanish (and English) grammar.