题目

老师问我们是否意识到预防压力的重要性。 The teacher asked ________ ________ ________ the importance of guarding ________ stress. 答案：if##whether     we     realized     against【解析】 【详解】 根据汉语可知，此句是 if或者 whether 引导的宾语从句，主句为一般过去时，从句也用过去的某一时态。 we“ 我们 ” ； realize“ 意识到 ” ，过去式为 realized ； guard against 表示 “ 预防 ” 。故填 if/whether ； we ； realized ； against 。_______,when Marx was already _______,he found it was important to study the situation in Russia, so he began to learn Russian.A. In 1870s, in his fiftiesB. In 1870s, in fiftiesC. In the 1870s, in fiftiesD. In the 1870s, in his fifties