我们现在必须离开，否则开会会迟到。

We must leave now, ___or ___else we'll be late for the meeting.

她警告我要努力学习，否则我可能会考试不及格。

She warned me to study hard, ___or ___else I might fail the exam.

按时付账单，否则会有罚款。

Pay the bill on time, ___or ___else there will be a penalty.