sad的副词形式是sadly。
sad；
adj.悲哀的;难过的;显得悲哀的;令人悲哀的;让人难过的;让人无法接受的;该受责备(或批评)的；
比较级： sadder；
最高级： saddest。
扩展资料
How sad that all his hard work should come to nothing.
他的'所有辛勤劳动竟全部付诸东流，太让人伤心了。
The increase in crime is a sad reflection on our society today.
犯罪的增加令人遗憾地反映了当今社会不太好的一面。
Its a sad fact that many of those killed were children.
让人难以接受的是遇难者中很多是孩子。
