They not walking over the bridge修改病句

They not walking over the bridge修改病句
They not walking over the bridge修改病句

They not walking over the bridge修改病句
They aren't walking over the bridge

not 改为are't

They didn't walk over the bridge.
walk over是瞬间动词，不能用进行时。

很明显的错误,缺少谓语啊!可以改成They are not.....

They aren't walking over the bridge