The more dangerous prisoners were kept chained. 比较危险的犯人被戴上镣铐。

chain sb/sth to sth Protesters had chained themselves to the railings. 抗议者们把自己缚在栏杆上。

chain sb/sth up rows of chained up bikes 几排锁在一起的自行车

With a major deadline to meet, Hannah had been chained to her desk all weekend. 为了赶上最后期限，汉娜整个周末都不得不伏案工作。