Use the first mouth shape to play single notes and the second one to play chord with tongue block.
吹十孔口琴一般都是用第一种，吹和弦或者使用舌堵法时就要用第二种口形了。
2
Conclusion: We use L as arch length and H as chord length to bend syringe needle that is used to posterior superior alveolar nerve block anesthesia by intraoral injection. The success rate is 98%.