contractions的例句（contractions在句子中的用法）

• Contractions are much more common in speech than in writing. 缩略词在口语里比在书写中常见得多.
• Foods and fluids are mixed in the stomach by its muscular contractions. 通过胃部肌肉的收缩食物和流质在胃中混合。
• Muscle contractions are powered by the chemical adenosine triphosphate ( ATP ). 肌肉收缩是由化学物质三磷酸腺苷 ( ATP ) 提供动力的.