How could you use the word main in a sentence but in an adjective way pls

My car is my main way of transportation.

An adjective is a describer.  Main means primary, so the "most typical"

The main reason he left the party was because he was tired

Even though there may have been other reasons to leave the party, the word main distinguishes that the fact he was tired was the biggest reason he left.

Hope this helps!

the answer is emerged from.

orpheus descended to hades, the world of the death to rescue eurydice. no mortal had ever done this before him, he survived because he was protected by the gods. the word "underworld" gives us a clue, he emerged from it like a whale emerges form sea for exemple.

the statement flat characters usually only have one trait that is developed in their story lines is true.