It should have set off an alarm bell, but it didn't.

他的画本来应该为我敲响警钟，但是我却没有意识到。

youdao

The drought and floods this year have set off an alarm about the threat that global warming poses.

今年的洪水和干旱对于全球变暖给人们带来的威胁拉响了警报。

youdao

Every hour, set an alarm on your computer or phone to go off.

在你的闹钟或者手机里设定一个以一个小时为间隔的停下来的时间。

youdao

If somebody does, an alarm is triggered, as a burglar might set off an alarm breaking into a house at night.

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His parents had to lock him in his room each night and place locks on his windows that would set off an alarm if he tried to open them during the night.

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When he went to the address indicated he had a look through the window then instructed the iPad to set off an alarm so that he could check that it was in fact his.

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