xiàn shàng huì yì kāi shǐ qián, xiān dǎ kāi liàn jiē, mài kè fēng hé shè xiàng tóu cè shì yī xià

线上会议开始前，先打开链接、麦克风和摄像头测试一下。

Before starting an online meeting, first open the link and test the microphone and camera.