You must develop the muscles of your speech organs to produce unfamiliar sounds.
所以你必须训练和发展你的发音器官(声带、舌、口、鼻腔等)的肌肉,以便发出陌生的(另外一种语言)声音。
I had forgotten all about the snails when Robert suddenly said that I must stay to dinner.
我把蜗牛的事已忘得一干二净,罗伯特突然提出一定要我留下来吃晚饭,这才提醒了我。