1. This is the first time that I have ever tasted this kind of food. (It is the first time that…)
2. Only in this way can you learn English well. (Only in this way can/will/…sb. do sth.倒装)
3. There is not much point in working on my PhD. (There is no point in doing…)
4. In this book, Hawking explains both what it means to be a scientist and how science works.
5. People who listen to Hawking’s lectures sometimes find it difficult to understand him.