实实在在从头学:backed up 的用法
1) backed up ( 马桶,水池,下水道堵塞)
e.g Toilet's backed up. 马桶堵住了
2) backed up (交通堵塞)
e.g. Cars were backed up for miles. 车堵了好几英里长。
e.g. Traffic is backing up on all out-of-town routes.所有出城的路都堵着呢。
3)backed up (订单处理堵塞)
e.g. Orders are really backed up this month. 这个月订单都积压住了