I have to work on weekends. I can't go on a picnic with them.
A. Unless I work on weekends, I can’t go on a picnic with them.
B. But for my work on weekends, I couldn't go on a picnic with them.
C. I wish I work on weekends, I can go on a picnic with them.
D. If only I didn't have to work on weekends and could go on a picnic with them.