What is the difference between explaining and supporting something ?

Explain, expound, explicate, elucidate, interpret mean to make something clear or understandable. explain implies a making plain or intelligible what is not immediately obvious or entirely known. explain the rules expound implies a careful often elaborate explanation.
Supporting : the act of showing that you believe that someone or something is good or acceptable : approval of someone or something. : the act of helping someone by giving love, encouragement, etc. : help that is given in the form of money or other valuable things.

Betray, destroy, and obey do not need to be changed to add the suffix -ed, because the "y" at the end of each word is preceded by a vowel  (so  they would be spelled  "betrayed," "destroyed," and "obeyed").

but hurry is different; it has to  be spelled "hurried" because the "y" at the end of "hurry" is preceded by a consonant.

It's a nonverbal que