1. They often clean their classroom after school . (改为被动语态)    
    Their classroom _____ often _____ by them after school.   
2. Li Lei gave Tom a new pen last week . (同上)    
    A new pen _____ _____ _____ Tom last week .   
3. A lot of people in China can speak English now . (同上)    
    English ______ ____ ______ by a lot of people in China now.   
4. I have learned English for about two years. (同上)    
    English _____ _____ _____ for about two years.   
5. They will publish these story-books next month. (同上)    
    These story-books _____ _____ _____ next month.