The risorius and the buccinator muscles assist in the retraction of the lips, as well as support entrapment of air within the oral cavity.
笑肌和颊肌帮助唇的收缩，也支撑了整个口腔的气
。
〕
;
驳;The risorius and the buccinator muscles assist in the retraction of the lips, as well as support entrapment of air within the oral cavity.
笑肌和颊肌帮助唇的收缩，也支撑了整个口腔的气。
声明：以上例句、词性分类均由互联网资源自动生成，部分未经过人工审核，其表达内容亦不代表本软件的观点；若发现问题，欢迎向我们指。
