Is this ungrammatical?

[Unregistered Lina]

Hello

I'd like to ask about "yet." Would you take a look at these sentences?
#1 Has it stopped raining yet?
#2 Have you done your homework yet?

In the question sentences you use "yet," right?
Can I omit "yet" in these sentences? Or are they ungrammatical?

Thank you.

[Tdol]

You can use it in questions and you can omit it in these examples.