when didnwe ever learn past tense?!
Well now you are!
Haha! Yeah you right.
Why can't it be singular? I wrote "З ким ти їсти обід?"
I reckon this should be accepted as well?
I think past tense singular would be "ти їв". I'm not good with cases, so I can't explain why "ти їсти" doesn't work.
When you say that, you're saying "Who do you eat lunch with," when it's asking you to translate "who did you eat lunch with." Thus - final translation becomes З ким ви їли обід? or even "З ким ви їв обід?
What's wrong with "З кім ти їв обід" ?
To answer my own question, "ким" not "кім"