>>9366472You have three simple ones to use two indefinite (a and an) and "the" as definite article.
The will be used for any object or being which can be classified into a group of something and recognized as a real existing thing in the current moment of any time by at least one or two observers, also what you will talking about is specific mostly just reserved for a single thing.
"The policeman questioned eyewitnesses for clues."
"The policeman" is different than "a policeman" in a manner that it means that "the policeman" is someone more important in the sentence, we know that guy longer than just the sentence want us to believe, it's a person recognized by us to be "the policeman" and not one of the other policemen over there.
A and an are indefinite and will be used to describe anything in any case, the thing which will be called with one of those isn't something special and it can be substituted with any other thing from the same sort."A" is used before a noun with a consonant sound and "an" before a vowel sound, reminder that the vowel sounding letters are (A I E O U), but not many know or even use this rule, there are other 20 different vowel sounds in English, taking this rule by thumb means if the word sounds like one of the vowel letters from the start it, an "an" will be used to name it in an indefinited case.
"A dog barks at ducks."
The dog isn't special for me, I just saw and heard this dog from a stranger barking at some random ducks, I will not interact with them.
>>9366663Let me some poste cringe
https://www.youtube.com/watch?v=OK2yqm-ofGA 
