There are glimpses of blue-green ice within the fissures, but the cracks themselves signal trouble.

在石块的裂隙中可以看到一些蓝绿色的冰块，然而这些裂隙本身就预示着麻烦。

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The coastguard received a signal saying the ship had engine trouble and that it had run aground just off the island of Sibuyan.

菲海上警卫队曾收到这艘船的信号，说她的引擎出现问题，正漂流在布延岛海岸。

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Similarly, at times, some problems may occur in the system even when there has been no check engine light or trouble code signal.

同样地，有时，有些故障可能在系统中已经产生但并没有“检查发动机”灯或故障码信号显示。

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The spike in Portuguese bond yields could signal trouble for Europe.

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But his sideline antics, which got him ejected from a game against Louisville, and the transfer of talented forward Gil Biruta after last season began to signal trouble.

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Why does the interloper effect signal trouble?

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