Use of the definite article

Can someone explain, please, what seems to me like a very arbitrary use of the definite article in Spanish. For example, in 12.3, entitled Chilean Literature, it says..." En mi familia, la literatura chilena...." meaning, " In my family, Chilean literature.....". Again, in 12.4, entitled Unforgettable Moments, it says " Mi mama iba a entrar a la universidad..." meaning..." My mom was going to start university..." But in 12.5 entitled How long ago did it happen, it says..." Cuando estas estudiando historia...." meaning, " When you are studying history....." There are many examples of this that I come across. Can I assume that where the definite article is used in English then it is used in Spanish, but that in the above examples it is optional?

I confuse the word in portuguese, because it has similarity with the spanish but I try to practice hard.

Buenos dias: If by definite article you mean... "El, La, Los, Las" then is not arbitrary, it just has to do with genders in spanish, everything has a gender so in this case "Familia", "universidad" and "Historia" are all feminine, hence the "la"...a good tip would be to check the way the word ends, ususally feminine end with "a" (familia, historia) the excepction here would be Universidad, which has an unusual ending, similar than "Facultad" (faculty), "Hermandad" (brotherhood) which are all "feminine". Hope this helps!!! @Reynaldo, indeed portuguese and spanish are very very similar, since they are both romance languages,

Hola Chicos, Great answer Christian. Jeffery, you might want to review lesson 10.1. The topic covers articles and it explains in detail what Christian said in his post. Hope it helps a little. :)

R is pronounced h in portuguese like carro.