He goes down to the basement and starts to check the wiring, and then gradually works his way up to the top of the building, apartment by apartment, checking every television, checking every connection, hoping to find out what this problem is.
于是他下到地下室检查电线 从那儿一路忙到楼顶， 挨家挨户地检查每一台电视 一台台地查 想找出问题所在