Questions & Answers about Estas necese, ke ni atendu ĝis nokto por vidi galaksion.
Why is it estas necese and not estas necesa?
Because necese is being used in an impersonal expression: estas necese = it is necessary.
In Esperanto, when there is no real noun being described, an -e form is often used:
- Estas grave. = It is important.
- Estas utile. = It is useful.
- Estas necese. = It is necessary.
By contrast, necesa is an adjective and normally describes a noun:
- La atendo estas necesa. = The waiting is necessary.
- Necesa paŝo = a necessary step
A very common alternative is also:
- Necesas, ke ni atendu...
That means essentially the same thing.
What does ke do in this sentence?
Ke introduces a subordinate clause, much like English that.
So:
- Estas necese, ke ni atendu...
= It is necessary that we wait...
In Esperanto, ke is normally required here. English often drops that, but Esperanto usually does not.
Compare:
- Mi scias, ke li venos. = I know that he will come.
- Estas klare, ke... = It is clear that...
Why is it ni atendu and not ni atendas?