adj.链接的；受束缚的
动词chain的过去式和过去分词.
Release the dog. He has been chained up for hours. 把狗放开，它已被拴了几个钟头了。
The dog was chained, so how did it get free? 狗拴著链子，是怎麽挣脱开的呢?
He chained his bicycle to the post. 他把自行车拴到柱子上。
He is chained to his work. 他工作忙得不能分身。
adj.解放的；无拘束的
动词unchain的过去式和过去分词形式.
