她用一根弹性带子捆扎那捆信件。

She wrapped an elastic ___band around the bundle of letters.

指导员用一根巨大的弹性带子进行安全练习。

The instructor used an enormous elastic ___band for the safety exercise.

一个紧绷的带子被绑在他的手臂上以止血。

A tight ___band was applied to his arm to stop the bleeding.