Human error may have been a contributing factor.

　　人為的失誤可能是一個起作用的因素。

　　We must allow for human error.

　　我們必須考慮到人為的失誤。

　　It was largely a matter of trial and error.

　　這主要是個反復實驗的問題。

　　He had made a humiliating tactical error and he had to go.

　　他犯了一個讓他顏面盡失的戰(zhàn)術錯誤，只得引咎辭職。