This is = To jest
Yes, but you can skip "jest" in that sentence. both
"To jest najszybszy pociąg w Polsce"
and "To najszybszy pociąg w Polsce"
mean exactly the same and both are correct
I agree, but to say that there is only one version is incorrect. And I got minus points for it. :(
:( keep in mind that the course is in beta and always report when you know you are right.