"Do you like salad with cabbage?"
Translation:Ви любите салат з капустою?
If you report such things (using the "report a problem" feature, not the comments), they'll be added to the database.
The course is still in Beta, and I've noticed that for now it's still very quirky regards liking/loving things; in Ukrainian it wants "любити" in most cases (and will often not yet accept the "подобається" form as it's not been taught yet), but conversely in English it usually expects "like" as a translation of it.
But as I say, just a matter of reporting as we go.
Ви - plural, formal Ти - singular, informal. I'm not a native speaker, but my girlfriend is. From what I understand you use Ви when speaking to strangers, positions of authority/elders or groups of people. Ти is for friends, family, children and singular use. At least that's my understanding.