simultaneously

• 一齐鼓掌

  clap hands in unison

• 一齐起哄

  all start laughing simultaneously

• 你们不要一齐说话。

  Don't talk at the same time.

• 大家一齐动手。

  Everybody got to work simultaneously.

• 队伍一齐出动。

  The troops are going into action simultaneously.

• 大家一齐出动，冒着零下三十度的严寒上伐木。

  Everybody set out simultaneously, facing bitter cold of minus thirty degrees to go and cut wood.