质疑答疑：face to face与face-to-face有何区别？
since 的用法有 哪些？
dare作为实义动词和情态动词有何区别？
专项训练：
1) 句型转换：
What you said made her angry. It was what you said that made her angry.
He experienced two World Wars. He went through two World Wars.
It happened that I was reading upstairs when he came in.
I happened to be reading upstairs when he came in.
He has a face-to-face interview with me.
He interviewed me face to face.
He didn’t dare to get close to the mad dog.
He dared not get close to the mad dog.
