sad的比较级为sadder。sad作为形容词，基本含义有“悲哀的”、“难过的”、“令人悲哀的”、“让人难过的”、“让人无法接受的”、“该受责备的”；而sadder作为比较级，含义有“让人更加悲哀的”、“令人相当难过的”等。
一、sad的中文含义及用法介绍
sad作为形容词，意为悲哀的;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。
例句：We are very sad to hear that you are leaving.
听说你要走了，我们十分难过。
It was sad to see them go.
看着他们离去，真让人难过。
It's 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。
You'd have to be sad to wear a shirt like that.
你穿着那样的衬衣显得老气。
It's a sad truth that children are the biggest victims of passive smoking.
不幸的事实是，儿童是被动吸烟的最大受害者。
二、sadder的中文含义及用法介绍
sadder作为sad的比较级，含义与sad相似，只是程度更深些。
例句：The porce left him sadder and wiser.
离婚使他痛苦，也使他长了心眼儿。
I drop my face in my hands for a longer and even sadder time.
我把头埋在手中，持续一段更长、更悲伤的时间。
It can shade one's outlook on the whole that the world is a sadder place.
这些都会从整体上塑造一个人的价值观，使他认为世界是一个悲伤之地。
Surely, he would have been a sadder child if they had.
如果他们真这样对他，他无疑是个不幸的孩子。
Consequently, come winter, we become sadder and sleepier.
因此，冬天到了，我们就会感到更悲伤，更加嗜睡。
