First of all, we should practice chest type (pectoralis major), which is divided into upper chest training and lower chest training. You are right to mention doing bench press to exercise Trieste. This part is mainly about training the upper chest, which means making your upper chest thicker and stronger. You mentioned that the effect of turning Briastra into a square chest with butterfly arms is also possible. This part is the muscle tissue that can be practiced to the whole pectoralis major. It will make your pectoralis major muscles more even. But your "lower chest" part has not been practiced at all, so there will only be cleavage in the middle, and the shape outside will not be obvious. I suggest that you can do "double-knife lower arm", mainly to practice the chest part. In fact, it's really a bit difficult for .......... to develop a thick square chest, because it depends in part on his natural constitution. Some people have practiced for a long time, and they have indeed formed a thick thorn, but .......... can't develop a square chest. The usual "pectoralis major" is that the upper chest is easier to practice and the lower chest is more difficult to practice. I hope the above can help you. You can add any questions. reference data