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高考 CET-4 CET-6 考研 IELTS GRE BNC: 1960 COCA: 2078
signal noun | verb | adjective
 1 
sig·nal / 5sIgnl ; 5sIgnEl /noun C
1. a sound or action that you make in order to give information to someone or tell them to do something信号; 暗号:
signal (for sb) to do sth
•When she got up from the table, it was obviously the signal for us to leave.她从桌边站起来，这显然是要我们离开。
•The headmaster gave the signal to begin.校长示意开始。
•At a prearranged signal the lights went out.预定的信号一发出，灯就全灭了。
⇒SMOKE SIGNAL
2. an event or action that shows what someone feels, what exists, or what is likely to happen信号; 标志; 预示:
signal (that)
•These results are a signal that the child may need special help.这些结果表明这个孩子可能需要特殊的帮助。
[+ of ]
•The opinion poll is a clear signal of people's dissatisfaction with the government.此次民意调查清楚地表明了民众对政府的不满。
•The display flashed a red warning signal .显示器闪了一下红色的警示信号。
•A red flag is often used as a danger signal.红色旗帜常常用作危险信号。
send / give a signal
•This will send the wrong signal to potential investors.这会给潜在投资者发出错误的信号。
3. a series of light waves, sound waves etc that carry an image, sound, or message, for example in radio or television〔无线电、电视等的〕讯号，信号:
send (out) / transmit / emit a signal (to sb)
•This new pay-TV channel sends signals via satellite to cable companies.这个新的付费电视频道通过卫星把讯号发送到有线电视公司。
•In the 1970s it was illegal to transmit fax signals via the public telephone system.20 世纪 70 年代用公共电话系统发送传真讯号是违法的。
receive / pick up / detect a signal
•a small antenna which receives radio signals接收无线电讯号的小型天线
•The Coast Guard picked up a distress signal from a freighter 50 miles out at sea.海岸警卫队接收到一艘离海岸 50 英里的货船发来的求救讯号。
4. a piece of equipment with coloured lights, used on a railway to tell train drivers whether they can continue or must stop〔铁路的〕信号灯，指示灯:
•a stop signal停车信号灯
•a signal failure (=when these lights do not work)信号灯故障
⇒busy signal at BUSY¹ (4)
 2 
signalverb
signalled, signalling BrE, signaled, signaling AmE
1. I,Tto make a sound or action in order to give information or tell someone to do something发信号，打信号; 示意:
•She signalled, and the waiter brought the bill.她打了个手势，侍者就拿来了账单。
•The whistle signalled the end of the match.哨声吹响，示意比赛结束。
[+ at ]
•Mary signalled wildly at them, but they didn't notice.玛丽拼命向他们做手势，但他们没注意到。
[+ to ]
•The judge signaled to a police officer and the man was led away.法官向一位警察示意，于是那个人就被带走了。
[+ for ]
•He pushed his plate away and signalled for coffee.他把盘子推开，并示意要杯咖啡。
signal (to) sb to do sth
•She signalled to the children to come inside.她示意孩子们进来。
signal that
•The bell signaled that school was over.铃声响起，放学了。
2. Tto make something clear by what you say or do – used in news reports〔用语言或行动〕表明，表示〔用于新闻报道〕:
•Both sides have signaled their willingness to start negotiations.双方都表明愿意开始谈判。
•British sources last night signalled their readiness to talk.英国方面昨晚表示愿意对话。
signal (that)
•The Prime Minister's speech today signals that there will be a shake-up in the cabinet.首相今天的讲话表明内阁将进行改组。
3. Tto be a sign that something is going to happen标志着，预示:
signal the start / beginning / end of sth
•the lengthening days that signal the end of winter白天变长标志着冬天的结束
4. Ito show the direction you intend to turn in a vehicle, using the lights〔车辆转方向时〕打灯示意;SYNindicate AmE:
•Signal before you pull out.驶离路边时先要打灯示意。
 3 
signaladjective only before nounformal
1. important重要的:
signal achievement / success / failure etc
•The university has done me the signal honour of making me an Honorary Fellow.这所大学给了我极大的荣誉，授予我荣誉董事的头衔。

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