cord grip lampholder- a lampholder incorporating a method of retaining a flexible cord by which it may then be suspended.
就是很早以前家里那种有根电线掉着一个灯座,固定在天花板上的那种
threaded entry lampholder - a lampholder incorporating a threaded component at the point of entry of the supply wires permitting the lampholder to be mounted on a mating threaded support.
就是台灯,那根金属杆上的灯座.