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- When a meter expires it could check for the presence of a car (by bouncing a signal off it) and report the expiration to the police. 当仪表到期，它可以检查一辆汽车的存在（反射过它的信号），并报告已经到期。
- to bounce a signal off a satellite 由通信卫星发射信号
- Another source is "scattering" of signals off the ionized trails left by meteors. 其它来源"驱散"信号被电离的足迹左由飞星。
- "Over the horizon" technologies - These facilitate ground-based methods of harassment (eg The Alaskan HAARP project which bounces signals off the ionosphere). “视距外”技术-这些促进了以地面为基础的折磨方法（例如阿拉斯加高频活跃极光研究计划，它反射信号到电离层）。
- Another technology under review is a space-based radar network that will continuously bounce signals off Earth's surface and under all conditions--even low clouds,storms,or darkness--detect moving targets such as trucks and missile launchers. 他们考虑的另一项技术是太空雷达网，它可以持续接收地球表面的反射信号，而且可以在任何情况下（即使在低云、暴风雨和黑暗中）发现卡车和导弹发射器等移动目标。
- A red light is usually a signal of danger. 红灯通常是危险的信号。
- Another technology under review is a space-based radar network that will continuously bounce signals off Earth's surface and under all conditions--even low clouds, storms, or darkness--detect moving targets such as trucks and missile launchers. 他们考虑的另一项技术是太空雷达网，它可以持续接收地球表面的反射信号，而且可以在任何情况下（即使在低云、暴风雨和黑暗中）发现卡车和导弹发射器等移动目标。
- I stood watching for the signal to change to green. 我站着等待交通信号转为绿灯。
- Let's set the clock by the radio time signal. 咱们照着收音机的报时信号把钟对一对。
- A red lamp is often a danger signal. 红灯常常是危险的信号。
- A reflected signal on a communication channel. 一种在通信信道上反射回来的信号。
- The rise in prices was a signal for rebellion. 物价上涨引起了叛乱。
- This train stops to let off passengers on signal. 这列火车按信号停车让旅客下车。
- A channel over which pilot signal is transmitted. 可在其上传输导频信号的一种信道。
- The signal pistol went off with a bang. 信号枪砰的一声响了。
- The signal was picked up by a downrange radar station. 该信号被试验飞行方向之内的雷达站收到了。
- The driver is winking his lights to signal a turn. 驾驶员打着一闪一闪的灯光信号表示要转弯。
- Everyone uncovered when the signal sounded. 信号响时，人人脱帽致敬。
- The train must stop when the signal's red. 信号机是红色时,火车必须停驶。
- A red lamp is used as a danger signal. 红灯用作危险信号。
- 今日热词
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- 深远海浮式风电平台 - deep-sea floating wind power platform
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- 京雄高速公路 - Beijing-Xiongan expressway
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- 农业及相关产业增加值 - the added value of agriculture and related industries
