link in binary tree

例句：

1. 1.The two computers are linked by a networkcable.
   这两台电脑通过一根网络线连接。
2. 2.The team members are linked together in achain.
   团队成员之间形成了一个链条。
3. 3. The newsoftware allows users to link their accounts together.
   新的软件允许用户将他们的账户链接在一起。