The rationale for this rule is that you cannot distinguish an inherited work item from a direct one at first sight.

此规则的基本原理是您不能立刻从直接工作项中区分继承的工作项。

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Motion across the line of sight can be followed by direct observation.

与视线垂直的运动可以通过直接观测得到。

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The biggest drawback to the technology is that it cannot travel through walls, because it requires a direct line of sight between the transmitter and the user's device.

这项技术最大的缺点是不能穿透墙壁，因为它要求发射器和用户设备可以通过直线连接。

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Now the camera can be triggered from up to 20 meters (66 feet) away, and a direct line of sight is not necessary.

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Infra-red communication suffers the same problems, but has the additional limitation of requiring a direct line of sight between objects as anyone who has tried to operate a television remote control with someone else standing between him and the television will know.

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But the developed world has lost sight of direct productive activity.

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