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。
Squeezing through a cleft in the rocks, the pot-holers arrived at an enormous cavern, the size of a huge concert hall.
洞穴探险者从岩石缝里挤身过去,来到一个巨大的洞里,其大小相当于一个音乐厅。