Private telephone lines operated on a system that precluded making or receiving international calls; international phone lines were available only under restricted circumstances.

私人电话线所连接的系统无法拨打或接听国际电话；国际电话线路只有在受到限制的场合下才会接通。

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Private telephone lines operated on a system that precluded making or receiving international calls;

私人电话线所连接的系统无法拨打或接听国际电话；

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The way most of these businesses operated was to take an order over the telephone and pass it on to a dispatcher, who then sent a radio message to find a free courier.

ECONOMIST: A courier company goes online