1、Don't forget what the sign said(改为反意疑问句)
Don't forget what the sign said, willyou?
祈使句的反义疑问句用will you,暗含主语是 you
2、Why don't you visit the zoo?(改为同义句)
Why not visit the zoo?
Why not = why don't
望采纳,祝开心~!