adj.被卡住的；塞满的
动词jam的过去式和过去分词.
He jammed his key into the lock. 他把钥匙卡在锁里了。
The newspapers were so tightly jammed in the letter-box he could hardly get them out. 报纸紧紧塞在信箱里，他很难取出来。
The landing-gear has jammed. 著陆装置发生故障。
As soon as she saw the child in the road, she jammed on her brakes. 她一见路上有个小孩，便猛踩刹车。
