Articles are so important that I know of a University in Eastern Europe that requires students to study article usage in English in a separate course. The course lasts an entire semester. It is one course that concentrates on article usage ONLY.
I'm going to talk about articles again in this post.
As I said in that previous post, even if you have articles in your native language, you need to learn how to use them in English. I've noted that in Spanish the usage is slightly different for certain situations.
However, if your native language doesn't have articles, then you must learn them, if you want to communicate without any confusion.
As you read any correctly written English, concentrate on the usage of articles. Think about how the article defines the noun that it is referring to.
In particular you should pay complete attention to each of my examples and explanations.
Here is a paragraph that talks about buying fruit. Concentrate, read it a few times, and read the explanation.
Today I went to the fruit and vegetable store. I bought apples, peaches, and bananas. The apples at the store were expensive, so I only bought the best ones. Most of the peaches were a little soft, so I really had to search and touch each peach that I bought. The bananas at the store were pretty good. So I'm confident that the bananas that I bought will last a few days.
"Today I went to THE fruit and vegetable store." "the" defines "store". In this case, it defines "store" as a store that the reader either knows about, or as a store that is the only one in my neighborhood. There are other cases, but they don't need to be discussed right now.
"I bought apples, peaches, and bananas." What? No articles? That's right, because I'm saying that I didn't really know what they would have. If I say "the apples, the peaches, and the bananas...", I'm saying that I knew they would have those items. Sometimes I go to that store and they don't have apples, or peaches, or bananas.
"The apples at the store were expensive, so I only bought the best ones." The first "The" defines all of the apples at the store as a single group. The third "the" defines a subset of those apples; the BEST apples (or "ones").
Notice in the last sentence: "...a few days." "a" is used even though the author is talking about plural days, because in this sentence, the author is talking about a group of days. “a” is used to make it known that the few days that they will last are not really clearly defined.
The use of few is something that you'll need to get used to. The proper way to use articles with "few" are not always clear to those who don't have a native feel for the language.
Remember, the only way to get a native feel for any language is to speak it and to somehow surround yourself with it.