4. When Mark walked in the street, he saw several fire engines fleeting by.
馬克經過那條街時,他看到了幾台消防車呼
5. It is important to be punctual.
6. It is the brave young man that rescued the drowning boy.
7. Mary is a good singer and an excellent dancer as well.
8. If I had known the result, I would not have spent so much money on it.
9. In 1998, he published his most famous book in his life.