Which sentence is the correct one? 1)you didn*t be in the party yesterday 2)you didn*t were in the party yesterday 3)you weren*t in the party yesterday

The correct sentence (верное предложение):
3) you weren*t in the party yesterday - глагол to be (were) сильный, он не может использоваться со вс глаголом did (а также с do и does)