课前回顾：
根据所给单词，在空格填入一个正确的形式。
1. We want to know _______(Canada) hobbies.
2. They might organize a stamp ________(collect) club.
3. She has taught ___________(she) English since she was fourteen.
4. He had fun _________(trade) stamps.
5. Making model train will be an __________(enjoy) hobby.
6. ________(learn) a new language is fun.
