1. Intense contraction of facial muscles, such as those used in signifying fear, heightens arousal. 面部肌肉因紧张而收缩会加强这种刺激，如人们感到恐惧时所表现出的肌肉收缩。
2. Snapping a photo directs attention, which heightens the pleasure you get from whatever you're looking at, Diehl says. 迪尔说，拍照能引导注意力，增加你从眼前的景象中获得的愉悦感。
3. "Snapping a photo directs attention, which heightens the pleasure you get from whatever you're looking at," Diehl says. 迪尔说：“抓拍照片能吸引注意力，增加你从所看事物中获得的愉悦感。”
4. The history of the conflict heightens it. 冲突的历史会加剧了两者之间的纠纷。
5. It heightens still further the sense of speed. 它进一步加强了速度意识。
