The airline delayed our flight because a mechanic found a crack in one propeller.

機械人員發現一具螺旋槳有裂痕，航空公司因此延誤了我們的班機。

Please email the supplier to confirm the replacement propeller ships by Friday.

請寄電子郵件給供應商，確認替換用的螺旋槳會在週五前出貨。

Our engineering team presented a quieter propeller design at this morning's meeting.

我們的工程團隊在今天早上的會議中展示了更安靜的螺旋槳設計。