用所给词的正确形式填空。(10分)
（1）The boys like to listen to music when they do ______ (they) homework.
（2）My mother's work is _____ (make) our city safe.
（3）One day, Mr Green asked Mrs Green ______ (go) shopping for him.
（4）We would brush our _______ (tooth) twice a day.
（5）This book is the lightest and ______ (thin) of all the books.
（6）She is ______ (good) than Alice at swimming.
（7）Janet ______ (get) up at 7:30 a.m. every day, so she is always late for school.
（8）I think the ______ (four) lesson is the most difficult in this book.
（9）Look at the sign. The library is _____ (close) from 1:00 p.m to 2:00 p. m.
（10）Jason is used to ______ (watch) TV the whole night.