“遗憾的”用英语怎么说？

遗憾的是，过于简单的情节使得这部电影差强人意。Sadly, the film is let down by an excessively simple plot.遗憾的是，这个快乐的故事结局却比较伤感。Unfortunately, this happy story finishes on a more sombre note.遗憾的是，附寄的照片不够清晰，无法复制。The enclosed photograph is unfortuna...