Off-line data transmission is simply the use of a telephone or similar link to transmit data without involving a computer system.

脱机数据传输是简单地利用电话或类似的链路来传输数据，不包括计算机系统。

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The line was cut off while I was talking to a friend by telephone.

在我和朋友通电话时线路被切断了。

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North Korea cut off a telephone hot line to the South and "declared invalid" the Korean War armistice, as the South Korean and U.S. began Monday a second phase of their annual joint winter military exercises.

WSJ: Pressure Rises on Korean Peninsula