1. 用所给的单词的适当形式填空

1. （1） —What are those in English?
   

   —  (it's) chairs.
   

3. （2） Look! My  (book) are on the sofa.

5. （3） My computer games (be) in the bag.

7. （4） His  (dictionary) are in my backpack.

9. （5） I (not) know she is your sister.