Before he left the room, he turned off all the devices to save electricity5/18Before he left the room, he turned off all the devices to save electricityAfter he turned off all the devices to save electricity, he left there.He left the room without turning off all the devices to save electricity.He left the room although he did not turn off all the devices to save electricity.Because he was in the right room, he turned off all the devices to save electricity.Giải thíchĐáp án đúng: A Dịch: Sau khi tắt hết đèn để tiết kiệm điện, anh ấy rời phòng.