be alarmed; 惊恐
With someone at his back, he does not fear anything.; feel reassured and emboldened 有恃无恐
threaten; intimidate 恐吓
I'm afraid it was not the original intent. 恐非原意。
There may be some other reason for it. 恐另有原因。
牛津高阶第八版
美国韦氏词典
Dictionary.com
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维基百科 (自由的百科全书)