on line意为“在运行,在运转;在网上”,例如:The new working methods will be on line in
June. / 新的操作方法将在六月启用。be on the line意为“有失去的可能;处在危险中”,例如:If we can't
succeed this time, my job is on the line. /要是我们这次不能成功,我就有失业的危险了。 所以应该将on
line换成on the line(means"facing some crisis/taking some risk")