他通过卧推和俯卧撑锻炼胸肌，三个月后肩背线条明显改善。
He worked out his chest with bench presses and push-ups, and after three months the definition of his shoulders and back had noticeably improved.
He worked out his chest with bench presses and push-ups, and after three months the definition of his shoulders and back had noticeably improved.