(    ) 1. The floor is very dirty. Will you please _________?

          A. to mop up it    B. mop up it      C. to mop it up        D. mop it up

 (    ) 2. The number of the red-crowned cranes will become ________ if we don't take any actions to protect them.

         A. fewer and fewer  B. less and less    C. smaller and smaller  D. larger and larger

 (    ) 3. Which symbol has the meaning of “per cent”?

         A. ©ƒ            B.££             C.¡ß                D. %