We talked about some question words back in February, but that doesn't cover all the types of questions you may need to ask.
For example we can turn any sentence into a question by adding 'nei' at the end.
Ei zopola ziti
I killed the bug.
O zopola ziti nei?
You killed the bug?
If you want to imply that the answer is yes we can change the verb to it's positive form.
O izopola ziti nei?
You killed the bug right?
If you want to imply that the answer is no we can change the verb to it's negative form.
O uzopola ziti nei?
You didn't kill the bug did you?
E... izopola. ...Oxida.
Um... I did. ...Sorry.