Ett or en
Hello, how to know when to use ett or en, for example ett äpple, en kvinna, en apelsin, I am not understanding when to use wich one...also the endings of “the” are different, when to use which one?
There is no major problem if you mix them up - as long as you are not using Swedish for professional purposes. The sentence is still understandable - however, in some cases you can turn singular into plural if you don't watch it. But don't worry about it and just take your best guess. Memorise which one it is, for the most commonly used nouns. These sorts of things come with exposure.
I don't think there is a shortcut for learning which gender to use with specific nouns -- you just need to memorize it for each one. I have found that once I use a noun long enough I soon remember which gender to use.
The general rule for "the" is that en nouns usually end with en and ett nouns usually end with et. For example, an orange = en apelsin, the orange = apelsinen, an apple = ett äpple, the apple = äpplet.
It's actually not a general rule, but rather always the case. En-words always form the definite with -en and ett-words form the definite with -et. The only differences from this occur when words already end with a vowel, in which case you might not need to add an extra "e" before tacking on "n" or "t" (like kvinna --> kvinnan).
Well, trying to treat English spelling and pronunciation as a whole, yes. But if you acknowledge that English words have different etymological roots (French, German, etc...) then the rules for spelling and pronunciation take on a much more solid rule system per each root language. This is why spelling bee champions ask for the country of origin when trying to spell a given word.
To complicate it further, we have "vacklande genus" for some nouns. This means that not everyone agrees on the grammatical gender for these words. Apelsin is one such noun so if you say "ett apelsin" it sounds really odd to me (and to most people), but you're not necessarily wrong.