(Korean) Is it hard to learn Korean? and which is harder writing in Korean, reading it, Or speaking it

Do the certificate in a summer course give credits? if so, how many credits? and also, could you tell me which are the summer course and schools you know that give credits?

Asevere storm that must commonly occurs in tropical regions is a(n)

Which verb mood would work best for expressing a wish that is unlikely to come true? indicative imperative conditional subjunctive