A GPRS device, which resembles a modem with an extended at command set, must define a context using an at command before it enters data mode.

GPRS设备类似于拥有扩展AT命令集的调制解调器，在进入数据模式之前必须使用AT命令定义一个上下文。

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The activities at Cwrt-y-Gollen army camp started with a group attempt at singing, before the men were set tasks including a wood-chopping race and a swamp command exercise using heavy sacks of coal.

BBC: The men had to carry coal sacks during one task