These are all words for an event, action or fact that shows that sth exists, is happening or may happen in the future. 以上各词均指迹象、征兆、预兆。

• sign an event, action or fact that shows that sth exists, is happening or may happen in the future 指迹象、征兆、预兆：◆Headaches may be a sign of stress. 头痛可能是紧张的迹象。
• indication (rather formal) a remark or sign that shows that sth is happening or what sb is thinking or feeling 指标示、象征：◆They gave no indication as to how the work should be done. 他们根本没说明这项工作该怎样做。

sign or indication? 用 sign 还是 indication？

An indication often comes in the form of sth that sb says; a sign is usually sth that happens or sth that sb does. * indication 常指通过某人说的话表明，sign 通常为发生的事或某人所做的事。

• symptom a change in your body or mind that shows that you are not healthy; a sign that sth exists, especially sth bad 指症状、征候、征兆：◆Symptoms include a sore throat. 症状包括嗓子疼。◆The rise in inflation was just one symptom of the poor state of the economy. 通胀上升不过是经济不景气的一个征候。
• symbol a person, object or event that represents a more general quality or situation 指象征：◆The dove is a universal symbol of peace. 鸽子普遍象征着和平。
• indicator (rather formal) a sign that shows you what sth is like or how a situation is changing 指指示信号、标志、迹象：◆the economic indicators 经济指标
• signal an event, action or fact that shows that sth exists, is happening or may happen in the future 指标志、预示、信号：◆Chest pains can be a warning signal of heart problems. 胸部疼痛可能是心脏病的报警信号。

sign or signal? 用 sign 还是 signal？

• Signal is often used to talk about an event, action or fact that suggests to sb that they should do sth. Sign is not usually used in this way. * signal 常用以指应该采取行动的暗号、信号；sign 通常不用于此义：◆Reducing prison sentences would send the wrong signs to criminals.

Patterns

• a(n) sign/indication/symptom/symbol/indicator/signal of sth
• a(n) sign/indication/symptom/indicator/signal that…
• a clear sign/indication/symptom/symbol/indicator/signal
• an obvious sign/indication/symptom/symbol/indicator
• an early sign/indication/symptom/indicator/signal
• an outward sign/indication/symbol
• to give a(n) sign/indication/signal