regretfully

1.The mate observed regretfully that he could not account for that young fellow’s whims.

那位伙伴很遗憾地说他不能说出那年轻人产生怪念头的原因。

2.regretfully, mounting costs and diminishing traffic forced the line to close.

令人遗憾，成增加和客量减少使航线被迫关闭。