撤消前有效指令的英文

• good till cancelled

• 前:    front
• 有效:    effective; valid; efficaciou ...
• 指令:    instruct; order; direct inst ...
• 撤消前有效:    gtc good till cancelled
• 取消前有效:    good till cancelled or countermanded; good until cancelled; good-till-cancelled; gtc