Questions & Answers about Vijak je kriv.
Je is the 3rd person singular present form of biti (to be).
So:
- vijak = screw / bolt
- je = is
- kriv = crooked / bent / at fault / guilty, depending on context
In this sentence, je simply links the subject and the description, just like is in English.
Because kriv has to agree with vijak.
Vijak is masculine singular, so the adjective is also masculine singular:
- masculine singular: kriv
- feminine singular: kriva
- neuter singular: krivo
- plural masculine: krivi
So:
- Vijak je kriv.
- Matica je kriva.
- Dete je krivo.
- Vijci su krivi.
There is also a second point: after je in a sentence like this, Serbian normally uses the short adjective form. So kriv is the expected form here.