选择合适的单词填空。
car museum insect museum science museum
如图所示为某宾馆的房卡．只有当房卡插入卡槽内．房间内的灯和插座才能有电。房卡的作用相当于一个____ （填路元件名称）接在干路上．插座、电视等用器，它们是____ 联．
—Sir, could I hand in my homework a bit late?
— __________, since you've been unwell these days.
的绝对值均正确）