| 摘要 |
The teaching and practice appts. for individual tennis practice has a tennis ball connected to the racquet by an elastic flexible line. The racquet end of the connecting line is attached to a bearing section which is made to swivel around the longitudinal axis of the tennis racquet handle. The tennis racquet handle has a ring groove located at the point where the handle runs into the frame section to accommodate the bearing section formed as a ring. The connecting line is attached to the bearing by an eyelet in the style of a pendulum. |
