shíyàn / kè / shàng / lǎoshī / ràng / wǒmen / yòng / diànjiàn / kòngzhì / diànlù / de / tōngduàn

实验课上，老师让我们用电键控制电路的通断。

During the lab class, the teacher had us use an electric key to control whether the circuit was open or closed.