I think you might be a little fat? If that's the reason, that's normal. If a fat person bends down, the burden on his waist will be heavy and he will instinctively be unwilling to bend down. If you don't bend down because you are fat, then you have to study hard and' experience' the basic posture of table tennis. In fact, the purpose of bending down to tuck in and lean forward is to move the body's center of gravity forward, which can also press the weight on the ball and increase the speed and rotation of returning the ball. There is also a' slightly bent knee', which aims to push the thigh down. At the moment of hitting the ball, you must push the ground and lean forward to return the ball well. If you stand too straight and don't lean forward, you can only produce upward force, but there is no forward force. It's a common mistake for the close-fitting ball to lean back sideways. This kind of mistake is not entirely your fault, but also the coach's. Again, I suspect that you are a little fat, which affects your moving speed. However, if we only pay attention to the practice of offensive movements and ignore the training of footwork, it will not work. Your wrong action is caused by poor footwork, not your habit. If you want to play table tennis well, you must be good at seven basic skills: blocking, pulling, rubbing, buckling, sending, receiving and footwork. Footwork practice is as important as others. I don't know if I'm right. Pure personal opinion, amateur. For reference only. Please don't laugh.