—Excuse me，could you tell me________a book about science？
—Sure．They are on the second floor．
| A．where I can buy |
| B．where can I buy |
| C．when can I buy |
| D．when I can buy |
Who is ________ swimmer, Peter, Simon or Millie？
| A．fast | B．the fastest | C．best | D．better |
I think maths is ________ than Chinese.
| A．more difficult | B．difficult |
| C．hard | D．easy |
There are lots of trees on ______ sides of the street.
| A．all | B．both | C．each | D．every |
My storybook is ______ in the bookshop.
| A．the most interesting | B．more interesting |
| C．the more interested | D．most interested |
She sings very well, because she has a good ________ .
| A．voice | B．noise | C．sound | D．face |