He took a microphone in his left hand and help up his right arm to ask for quiet.

他左手拿起麦克风，然后举起右臂示意大家静下来。

youdao

If needed, staff in a control centre can see and hear everything the field engineer is seeing and hearing via the camera and microphone mounted on the robot arm.

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He waves an arm and croons into a microphone no worries, amplification is not used as eight dancers shake large yellow-and-orange feathers.

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