第1题: [单项选择]I left for the office earlier than usual this morning ______ traffic jam. A. in case of B. for the sake of C. in line with D. at the risk of 参考答案:A 答案解析:本题考查介词短语辨析。四个选项的意思分别为:in case of“万一,以防”,for the sake of “为了,为....的利益”,in line with“符合,与....一致”,a