1. Our dean is an understanding counselor, not a martinet.
    我们的教务长是一位善解人意的好顾问，而非厉行严格纪律者。

2. I said that if he talked very long, his Russian listeners, not understanding what was said, would probably lose interest.
    我说如果他讲很长时间，而他的苏联听众们听不懂他的谈话，就很可能会失去兴趣。

3. If they experience technical difficulties, or problems in understanding something about the course, they MUST speak up; otherwise there is no way anyone can know something is wrong.
    如果碰到技术方面的问题，或在理解课程中遇到困难，必须直接说出来。否则任何人都无从知晓问题所在。