1)My sister bought a new dress (+)
My sister didn't buy a new dress (-)
Did your sister buy a new dress? (?)
2)My brother worked yesterday (+)
My brother didn't work yesterday (-)
Did your brother work yesterday? (?)
1)My sister bought a new dress (+)
My sister didn't buy a new dress (-)
Did your sister buy a new dress? (?)
2)My brother worked yesterday (+)
My brother didn't work yesterday (-)
Did your brother work yesterday? (?)