下列各句均有一处错误，请将序号填入括号并改正。

( ) 1. What did you do yesterday ?    I listen to music.                         

                      A         B                          C

(     ) 2. Did  you helped them clean their room ?                                     

              A             B               C

(     ) 3. Wu Yifan play football with his friends.                                     

                            A                 B            C

(     ) 4. Yesterday is his grandma's birthday.                                           

                 A        B            C

(     ) 5. Its tail is about 38kg long.                                                         

                  A                B      C