这篇文档是关于大连理工大学2020年春季学期《大学英语4》在线测试1的答案，主要涉及了多项选择题的解答。以下是对其中部分题目及其相关知识点的详细解析：
1. 题目：Though he didn't answer my questions quickly, the look on his face () that he was satisfied with me.
- 答案：A. indicated
- 知识点：此题考察动词的用法。indicated 表示“表明”，在这里正确地表达了对方脸部表情所透露出的满意情绪。
2. 题目：The children () many times not to play with fire.
- 答案：C. have been told
- 知识点：这道题考察时态和语态。children 和 tell 之间是被动关系，且强调多次告知，所以使用现在完成时的被动语态。
3. 题目：Jack is a strong (), but you could beat him if you perform at your highest level.
- 答案：A. opponent
- 知识点：opponent 意为“对手”，符合上下文中的比赛或竞争场景。
4. 题目：Poor children are less likely to complete high school or to enroll () college.
- 答案：B. in
- 知识点：enroll in 表示“注册，报名”，常用于表示入学或参加课程等。
5. 题目：He said that I had stolen his bicycle, but I () it.
- 答案：D. denied
- 知识点：deny 表示“否认”，在这里用于反驳对方的指控。
6. 题目：How can you keep the machine () when you are away?
- 答案：C. running
- 知识点：keep sb./sth. doing 表示“使某人/某物持续做某事”，running 表示机器持续运行。
7. 题目：I love my hometown () it is a beautiful place.
- 答案：C. because
- 知识点：because 引导原因状语从句，解释爱家乡的原因。
8. 题目：After driving for thirty miles, she suddenly realized that she () in the wrong direction.
- 答案：C. had been driving
- 知识点：此处表示过去的过去，即在意识到之前一直在错误的方向驾驶，所以使用过去完成进行时。
9. 题目：Your proposal () by the committee soon.
- 答案：C. is going to be discussed
- 知识点：根据soon可知，讨论提案的动作即将发生，所以使用一般将来时的被动语态。
10. 题目：The problem is () it may take time for new facts to become available.
- 答案：A. that
- 知识点：that引导表语从句，在这里没有实际意义，仅起连接作用。
11. 题目：Jack () and he can't find the way back to the hotel.
- 答案：D. is lost
- 知识点：be lost 表示“迷路”，固定搭配。
12. 题目：I didn't do it () purpose; it was an accident.
- 答案：D. on
- 知识点：on purpose 表示“故意地”，与后面的accident形成对比。
13. 题目：She broke () in tears when she heard the news.
- 答案：D. down
- 知识点：break down in tears 表示“忍不住哭起来”。
14. 题目：That seemed impossible dream about flying has ___________ true.
- 答案：A. come
- 知识点：come true 表示“实现”，梦想成为现实。
15. 题目：The fact () remains we are behind many others.
- 答案：A. that
- 知识点：that 引导同位语从句，解释the fact的具体内容。
16. 题目：Before he came to New York, he had never heard a ...
- 知识点：本题未给出完整信息，但可以看出在谈论他来纽约之前的事情，可能涉及过去完成时态。
以上就是部分题目及涉及的英语语法和词汇知识点，这些题目涵盖了动词时态、语态、固定搭配、名词性从句等多个方面，对学习者来说是很好的练习材料。
