the legend of the corn

The ancient mayan myth says that one day a young boy that was a prince in a city was given in marrige to another young girl, princess of another city.
The parents of the oyung girl sent her to the city of the little boy.
The parents of the young boy sent the couple to a sacred place so they give them luck to have a kid.
They waited three days to see them again, but when they got to the place they don't see the couple, but saw two corn cornfields  where they seen the couple last time.

modal verbs

Have to	should	must
Have to" is used to express certainty, necessity, and obligation.	"Should" is most commonly used to make recommendations or give advice.	Must" is most commonly used to express certainty.
Behaves quite irregularly in the past and the future.	It can also be used to express obligation as well as expectation	It can also be used to express necessity or strong recommendation, although native speakers prefer the more flexible form "have to."